How to file a mechanics lien in District of Columbia

Step by step

13 steps for a subcontractor in District of Columbia.

1. 1

   Step 1: Check you are close enough to the owner to have a lien

   Before you sign the contract. Then check again the day you decide to file.

   DC gives a mechanics lien to exactly two groups: the contractor who signed with the property owner, and anyone that contractor hired directly — subcontractor, material supplier or laborer. That is the whole list. If you were hired by a subcontractor, or you sold material to a subcontractor, you have no DC lien. Not a weak one. None.

   Where it goes

   Your own contract file, and a written question to whoever hired you.

   How

   Look at your own contract or purchase order. Whose name is on the other side? Then ask that party, in writing, who they signed with. If their answer is anyone other than the property owner, you are second tier.

   Proof to keep

   Your signed contract or accepted purchase order showing exactly who hired you, plus any email or letter in which they identify the original contractor.

   What the document must contain

   • Who hired you, by exact legal name
   • Who that party contracted with
   • A copy of the owner-contractor agreement if you can get one

   If you miss it: If you are second tier or lower and you record anyway, you have recorded a void document. You get nothing from it, you have spent your money and attention on it, and you have clouded someone's title without a right to — which invites a slander-of-title claim back at you.

   D.C. Code § 40-303.01; D.C. Code § 40-301.01(opens the statute in a new tab)
2. 2

   Step 2: Find out who owns the land before you count any lien deadline

   Before you start. Then the moment payment stops, because the bond clocks are already running off your last day on site.

   No mechanics lien attaches to property owned by the District of Columbia or by the federal government, and DC has an unusual amount of both. On those jobs your money comes from a payment bond, and the deadlines are different numbers running from a different date: written notice to the prime contractor within 90 days of YOUR last day of work or last delivery, and suit within one year of that same date. Both clocks run from your own last day, not from anybody's filing.

   Where it goes

   District job: notice to the prime contractor; suit in the Superior Court of the District of Columbia, brought in the name of the District for your use. Federal job: notice to the prime; suit in federal district court.

   How

   Ask the prime contractor or the contracting officer for a copy of the payment bond. For a District job, a payment bond is required on construction contracts over $25,000. If you have no direct contract with the prime, send the 90-day notice by registered mail (District job) or by a method giving written third-party proof of delivery (federal job) to the prime's office, place of business or residence. A first-tier sub to the prime does not need the 90-day notice, but still has only one year to sue.

   Proof to keep

   The registered-mail receipt or third-party delivery verification, a copy of the notice, the bond, and dated delivery tickets or timesheets fixing your last day.

   What the document must contain

   • The amount you claim, stated with substantial accuracy
   • The name of the party you supplied or worked for
   • Written form, dated, and sent by a method the statute allows

   If you miss it: You recorded a notice of intent that attaches to nothing, and while you were doing that the 90-day bond notice expired. On a District or federal job the lien paperwork is not just useless — it burns the only window that mattered.

   D.C. Code §§ 2-201.01, 2-201.02 (District projects); 40 U.S.C. § 3133(b)(2), (b)(4) (federal projects)(opens the statute in a new tab)
3. 3

   Step 3: Get your DC licence and certificate of good standing current now, not later

   Before you ever need to file. The good-standing certificate has to be less than 180 days old on the day you record, so pull a fresh one when the job starts going bad.

   A DC notice of intent must have your licence paperwork attached. If you are a DC entity or doing business in DC, you attach your current DC business licence AND a certificate of good standing issued within 180 days before you file. If you are an out-of-jurisdiction claimant not doing business in DC but licensed somewhere, you attach your home-state licence and a home-state good-standing certificate. Missing paperwork does not delay the filing — it voids it.

   Where it goes

   DC Department of Licensing and Consumer Protection (DLCP).

   How

   Business licence from the DC Department of Licensing and Consumer Protection. Good-standing certificate through DLCP's BOSS system (formerly CorpOnline) at boss.dc.gov — select Certificates & Certified Copies, then Good Standing Certificate. Note that a good-standing certificate cannot be issued for a trade name, only for the registered entity.

   Proof to keep

   The dated certificate itself, and the receipt showing when you pulled it. The date on the certificate is what proves the 180 days.

   What the document must contain

   • Copy of your current licence to do business in DC issued by DLCP (or your home jurisdiction's current licence if you are out of jurisdiction)
   • Certificate of good standing from DLCP issued within 180 days before the filing date (or your home jurisdiction's good-standing certificate)

   If you miss it: Your notice of intent does not comply with § 40-301.02(b) and is therefore void by the plain words of § 40-301.02(a)(1). If the 90 days has run, there is no second filing and no amendment. The lien is gone over a piece of paper you could have pulled in an afternoon.

   D.C. Code § 40-301.02(b)(7)(A), (B)(opens the statute in a new tab)
4. 4

   Step 4: On residential home improvement work, get the contract in writing on the District's approved form

   Before the first day of work. You cannot create this document later.

   This step only applies if the job is home improvement — repair, remodeling, alteration, conversion or modernization of, or an addition to, residential property. DC requires a copy of the home improvement contract to be attached to the notice of intent. A 'home improvement contract' under DC law is a WRITTEN agreement on a form approved by the Department of Buildings, and every contract between the same contractor and the same homeowner inside any 12-month period is treated as one contract for one price. Separately, residential home improvement work requires a Home Improvement Contractor licence from DLCP, backed by a $25,000 surety bond for the two-year licence period.

   Where it goes

   Your contract file; DLCP for the Home Improvement Contractor licence and bond.

   How

   Use a Department of Buildings-approved contract form and have the homeowner sign it. Keep the original. If you are a sub on a home improvement job, ask the general contractor for a copy of their home improvement contract with the homeowner now, while they are still speaking to you.

   Proof to keep

   The signed contract, any change orders, your Home Improvement Contractor licence and the $25,000 bond.

   What the document must contain

   • A written home improvement contract on a Department of Buildings-approved form
   • A specific price
   • All work for the same homeowner in the same 12-month period aggregated into that one contract

   If you miss it: You have nothing to attach under § 40-301.02(b)(8), so your notice of intent is void under § 40-301.02(a)(1) and your lien is gone. A contractor who worked a residential job on a handshake has no compliant notice to file, at any price. There is also serious exposure on the licensing side for unlicensed home improvement work — get a lawyer before you file if you were not licensed.

   D.C. Code §§ 40-301.02(b)(8), 40-301.03(1), 40-301.03(2); 16 DCMR ch. 8(opens the statute in a new tab)
5. 5

   Step 5: Put a written notice of what you are owed in the owner's hands — early, and again every time it grows

   There is no day count in the statute, and that is exactly the danger. The deadline is not a date — it is the owner's last cheque to the GC, which you will never see coming. Send it as soon as an invoice goes past due, and refresh it whenever the balance grows.

   This is the single most important thing a DC sub or supplier can do, and almost nobody does it. Under § 40-303.02(b), once the owner has paid the general contractor in full in good faith, everyone the GC hired loses their lien completely — even if your 90 days is still wide open. Your only protection is a written notice to the OWNER stating the amount you are owed, delivered while the owner still owes the GC at least that much. Once the owner has that notice, any later payment to the GC is presumed not to have been made in good faith, and your lien survives. The notice only protects the amount you stated, so send a new one whenever the number goes up. No contract can stop you: any clause forbidding you from contacting the owner is void to the extent it blocks this notice.

   Where it goes

   The property owner directly — not the general contractor, and not the owner's construction manager only. Get the owner's current address from the DC land records.

   How

   A dated written letter to the owner. Send it certified mail return receipt requested, and email it too. Get it into their hands, not just into the mail.

   Proof to keep

   The certified mail green card or tracking showing delivery, the dated letter, and the email with its send receipt. The date of delivery is what beats the owner's cheque.

   What the document must contain

   • Your name and contact details
   • The property address
   • What you supplied or did
   • The exact dollar amount currently due and unpaid (the 'notice amount')
   • The date

   If you miss it: The owner pays the GC in full, the GC does not pay you, and you have no lien. Not a late lien — no lien. And under § 40-303.19 you cannot get a personal money judgment against the owner either, absent a written promise from them supported by consideration. You are left chasing a general contractor who already has the money.

   D.C. Code § 40-303.02(b)(opens the statute in a new tab)
6. 6

   Step 6: Ask the owner in writing what the GC's contract says and what is still unpaid

   Optional

   Any time you are worried about getting paid — ideally the same day you send the notice of amounts due.

   DC gives subs a lever most states do not. You can demand from the owner a statement of the terms the work is being done under and the amount still due or to become due to the general contractor. If the owner refuses to answer, or answers falsely about the terms or the unpaid balance, the property becomes liable to your lien 'in the same manner as if no payments had been made to the contractor' before you served the owner. That turns the owner's silence into your best evidence.

   Where it goes

   The property owner or the owner's authorized agent.

   How

   A dated written demand to the owner or the owner's authorized agent, sent certified mail return receipt requested.

   Proof to keep

   The demand letter, proof of delivery, and whatever the owner did or did not send back. Silence is worth keeping.

   What the document must contain

   • A request for the terms under which the contracted work is being done
   • A request for the amount due or to become due to the contractor
   • Your identity and the property address
   • The date

   If you miss it: Nothing is forfeited — this is an extra weapon, not a deadline. But you go into a dispute blind about how much money is actually left in the job, and your lien is capped at that unknown number anyway.

   D.C. Code § 40-303.05(opens the statute in a new tab)
7. 7

   Step 7: Build the notice of intent so it cannot be void

   Assemble it before you are close to day 90. Getting a notary, a licence copy and a fresh good-standing certificate on the same afternoon is not realistic.

   DC does not forgive form errors. The statute says a notice of intent that does not comply with subsection (b) 'shall be void.' There are nine required items and all nine are mandatory. Two catch people out. First, the amount must be NET — the amount claimed 'less any credit for payments received up to and including the date of the notice of intent.' Rolling a gross invoice total forward is not an overstatement you can trim later; it is a defect that voids the whole notice. Second, work dates and material dates are separate items: you need the dates work was commenced and completed AND the dates material was first and last delivered.

   Where it goes

   Your own desk, then a notary.

   How

   Draft it, get the sworn statement notarized, and attach every exhibit. If you sign as a representative or through counsel, attach written evidence of your authority to sign.

   Proof to keep

   A complete copy of exactly what you recorded, with every exhibit, plus the ledger showing how you calculated the net amount.

   What the document must contain

   • (b)(1) Your name and address, or your registered agent's
   • (b)(2) The owner's name and address, or the owner's registered agent's
   • (b)(3) The name of the party against whose interest the lien is claimed, and the amount claimed LESS any credit for payments received up to and including the date of the notice
   • (b)(4) A description of the work done, including the dates work was commenced and completed
   • (b)(5) A description of the material furnished, including the dates material was first and last delivered
   • (b)(6) A legal description of the property and, to the extent available, the street address
   • (b)(7) Your current business licence and a certificate of good standing issued within 180 days (or the out-of-jurisdiction equivalents)
   • (b)(8) A copy of the home improvement contract, if the project was provided under one
   • (b)(9) A sworn, notarized statement under penalty of perjury and on personal knowledge that the notice is true and correct and that you have a right to recover the amount claimed — plus evidence of authority if a representative or counsel signs

   If you miss it: The notice is void. Not defective, not amendable — void. If the 90 days has expired, so has your lien, and the Recorder of Deeds accepting your paperwork at the counter means nothing: the office records documents, it does not certify that yours complies.

   D.C. Code § 40-301.02(a)(1), (b)(1)-(9)(opens the statute in a new tab)
8. 8

   Step 8: Record the notice of intent — within 90 days, and much sooner if you can

   Any time during construction, or within 90 days after the earlier of completion or termination of the project. If you are unpaid and the job is winding down, record now.

   Record your notice of intent in the DC land records. The law lets you record at any time DURING construction, or within 90 days after the earlier of completion or termination of the project. Read that again: the earlier of completion or TERMINATION, and of the PROJECT, not of your own scope. An owner can terminate the general contractor without telling you, and your 90 days starts that day whether you hear about it or not. Recording during construction is expressly permitted and is the only reliable defence.

   Where it goes

   DC Office of the Recorder of Deeds, 1101 4th Street SW, 5th Floor, Washington DC 20024. Phone (202) 727-5374. There are no counties in DC — this one office covers the whole District.

   How

   Record in person at the Recorder of Deeds, or eRecord through one of the office's approved vendors (CSC/Ingeo, Simplifile or ePN — the office accepts all document types for eRecording). The recording fee for a document that is not a deed of trust or mortgage is $25, plus a $5 per-document surcharge, so $30. Notarize and record in the same week: the office's general recording rules state a $250 late fee for documents recorded more than 30 days after signing and notarization, and it is not worth finding out whether they apply it to a lien notice.

   Proof to keep

   The stamped recorded copy showing the instrument number and the exact date and time of recording. That date is what starts your 180 days and your 5 business days — write it on the front of your file.

   What the document must contain

   • The complete notice of intent with all nine § 40-301.02(b) elements and every exhibit
   • A clear return-to mailing address
   • Notary seal, signature, printed name and commission expiry on the sworn statement

   If you miss it: The statute is blunt: if the notice of intent is not recorded during construction or within the 90 days, 'the contractor's lien shall terminate upon the expiration of the 90-day period.' There is no extension, no excuse for not knowing the job was terminated, and no second filing.

   D.C. Code § 40-301.02(a)(1); D.C. Code §§ 42-1210, 42-1211 (fees and surcharge)(opens the statute in a new tab)
9. 9

   Step 9: Mail the owner a copy by certified mail within 5 business days — and post it on the property if it bounces

   Within 5 business days after the date of recording. Count business days, not calendar days, and start from the recording date stamped on your copy.

   Recording is only half the filing. Within 5 business days of recording you must send the owner a copy of the recorded notice of intent by certified mail, to the owner's current address from the local public records, or their last known address if the records do not have one. There is a second half most claimants skip: if the certified mail comes back unclaimed or undelivered, you must physically post a copy of the recorded notice on the property, in a spot generally visible from an entry point.

   Where it goes

   The owner's current address as shown in DC public records; failing that, their last known address. If it bounces, the property itself.

   How

   Certified mail. Keep the receipt. If the envelope comes back, drive out and post it, and photograph it in place with a date.

   Proof to keep

   The certified mail receipt and tracking printout, the returned envelope if it comes back unopened, and dated photographs of the posted copy showing the property and the entry point.

   What the document must contain

   • A copy of the RECORDED notice of intent, with the recording stamp — not your unrecorded draft

   If you miss it: You have not done what § 40-301.02(a)(2) requires of a contractor who records a notice of intent. The owner will raise it, and you will be arguing about whether your lien survives a step you could have completed with a trip to the post office.

   D.C. Code § 40-301.02(a)(2)(opens the statute in a new tab)
10. 10

    Step 10: Hand-serve the recorded notice on the owner — every day you wait costs you money

    The same day you record, or as close to it as you can manage. There is no stated day count — there is just money draining out of the job while you wait.

    If you were hired by the general contractor rather than the owner, you have a SECOND service duty on top of the certified mailing. You must serve the recorded notice on the owner by leaving a copy with the owner or the owner's agent, if either lives in the District, or by posting it on the premises if neither can be found. This is not a formality. Until you serve it, the owner may keep paying the general contractor under their contract, and every one of those payments reduces the amount your lien can reach, dollar for dollar. Once you have served it, the owner is bound to hold back enough out of later payments to cover what the GC owes you.

    Where it goes

    The owner or the owner's agent, in the District; otherwise the property itself.

    How

    Leave a copy with the owner or the owner's agent in person. If neither is a DC resident or neither can be found, post it on the premises and photograph it.

    Proof to keep

    A signed acknowledgment of receipt if you can get one, an affidavit of service from whoever delivered it, or dated photographs of the posting. Keep the date — it is the line between payments that reduce your lien and payments that do not.

    What the document must contain

    • A copy of the RECORDED notice of intent
    • A record of who you handed it to, where and when

    If you miss it: The owner keeps paying the GC lawfully, and your lien shrinks with each payment until there is nothing left to secure. You can hold a validly recorded, perfectly drafted lien worth zero dollars because you waited three weeks to serve it.

    D.C. Code §§ 40-303.03, 40-303.04(opens the statute in a new tab)
11. 11

    Step 11: File suit to enforce within 180 days of recording

    Within 180 days after the date the notice of intent is recorded in the land records. Get a lawyer engaged by day 120 at the latest — you also have a 10-day recording step the moment you file.

    Recording preserves the lien; it does not collect anything. You must file suit to enforce it within 180 days after the DATE THE NOTICE OF INTENT WAS RECORDED — not 180 days from completion, not from your last invoice, not from the day the owner stopped answering. The proceeding is a bill in equity asking the court to sell the owner's interest in the property and apply the proceeds to your lien. If anyone other than the principal contractor brings the suit, the principal contractor must be named as a defendant, along with everyone else who has recorded a lien on the property. Several lienholders on the same property may join in one suit.

    Where it goes

    Superior Court of the District of Columbia.

    How

    Through counsel. This is a court filing, not a form.

    Proof to keep

    The stamped complaint with its filing date and docket number — you need both within the next 10 days.

    What the document must contain

    • A brief statement of the contract the claim is founded on
    • The amount due
    • The date the notice was filed with the Recorder of Deeds
    • The date a copy was served on the owner or the owner's agent, if it was
    • The date the building or the work on it was completed
    • A description of the premises and the other material facts
    • A prayer that the owner's interest be sold and the proceeds applied to the lien
    • The principal contractor named as a defendant if you are not the principal contractor, plus all others who recorded liens

    If you miss it: The lien terminates. § 40-303.13(a)(2) says so directly: failure to file suit within the 180-day period terminates the lien. There is no renewal and no re-recording.

    D.C. Code §§ 40-303.13(a)(1)(A), 40-303.08(opens the statute in a new tab)
12. 12

    Step 12: Record the notice of pendency of action within 10 days of filing suit

    Within 10 days of filing suit. Calendar it the same hour the complaint is stamped.

    This is the step that kills DC liens held by people who did everything else right. Filing suit is not enough. Within 10 days of filing, you must also record a notice of pendency of action in the land records. The statute is explicit that failure to file suit in time OR to file a timely notice of pendency 'shall terminate the lien.' Sue on day 179 and record the pendency notice on day 11 after filing and you have forfeited everything.

    Where it goes

    DC Office of the Recorder of Deeds, 1101 4th Street SW, 5th Floor, Washington DC 20024 — the same office where you recorded the notice of intent.

    How

    Prepare the notice in writing, sign it (you or your counsel), have it notarized, and record it with the Recorder of Deeds.

    Proof to keep

    The stamped recorded notice of pendency showing its recording date, kept alongside the stamped complaint. Those two dates, 10 days apart or less, are your proof.

    What the document must contain

    • In writing, signed by a party or counsel, and notarized
    • The name of the court where the action is filed
    • The title of the action or proceeding
    • The docket number
    • The date of filing
    • The object of the filing
    • The amount of the claim asserted, or the nature of any other relief sought
    • The name of the person whose estate is affected
    • A description of the real property affected

    If you miss it: The lien terminates by operation of § 40-303.13(a)(2), even though your suit was filed in time and is still alive. You keep whatever contract claim you have against whoever hired you, but the property is no longer security for it.

    D.C. Code § 40-303.13(a)(1)(B); D.C. Code § 42-1207(b)(opens the statute in a new tab)
13. 13

    Step 13: Expect the owner to buy the lien off the property — and keep going anyway

    Any time. You will get notice of it — take the notice seriously and do not treat it as the end of the matter.

    DC has no notice of contest and no procedure for an owner to force you to sue early. What the owner does have is money. The owner can pay the amount you claim into court, plus whatever the court directs for interest and costs, or post a written undertaking with sureties. Either one releases the PROPERTY from your lien. The owner can do this before you ever file suit, or after. Your claim is not extinguished — it moves from the building to the fund or the bond, and you still have to sue within your 180 days and record your pendency notice within 10 days of filing, exactly as before. The sureties must each swear they are worth, over and above all debts and liabilities, double the amount of the lien, and you have the right to object to them.

    Where it goes

    Superior Court of the District of Columbia.

    How

    Read the notice you receive. Check the sureties. Object if they are thin. Then carry on with your suit against the fund or the bond.

    Proof to keep

    The notice you received, the undertaking or proof of payment into court, and the surety affidavits.

    What the document must contain

    • The owner's payment into court, or a written undertaking with approved sureties
    • Notice to you as the lienor
    • Surety oath that each surety is worth double the amount of the lien over and above all debts and liabilities

    If you miss it: If you treat a bonded-off lien as a closed file, your 180-day suit deadline and 10-day pendency deadline run out against a fund you could have collected from. The security changed form; your deadlines did not.

    D.C. Code §§ 40-303.16, 40-303.17(opens the statute in a new tab)

Who can claim a lien in District of Columbia

Where you file

Office

District of Columbia Office of the Recorder of Deeds (Office of Tax and Revenue), 1101 4th Street SW, 5th Floor, Washington, DC 20024; (202) 727-5374

Recording fee

$30

Notarization

Required

Sworn or verified

Sworn notarized statement under penalty of perjury upon personal knowledge

How it is served

Certified mail

Copies

1

Fees and office procedures change; confirm them with the recording office before you file.

What trips people up in District of Columbia

• Believing the 90 days is your safety net. It is not, if you are a sub or supplier. Under § 40-303.02(b) the owner paying the general contractor in full in good faith ends your lien right completely, and nothing in the statute makes them tell you they did it. A notice of intent recorded on day 89 is worthless if the owner paid out on day 60. Get a written notice of what you are owed to the OWNER as early as you can, and update it as the number grows.
• Assuming you have a lien because you worked on the building. DC gives lien rights only to the contractor who signed with the owner and to people that contractor hired directly. A sub hired by a sub, or a supplier who sold to a subcontractor, has nothing under § 40-303.01. Recording anyway produces a void instrument and an invitation to a slander-of-title claim.
• Waiting for the job to be 'complete.' § 40-301.02(a)(1) starts the 90 days at the earlier of completion or TERMINATION of the project. An owner can terminate the GC in a phone call and never tell the subs. Recording during construction is expressly allowed — do it as soon as you are seriously unpaid.
• Counting 90 days from a punch-list visit or a warranty call-back. The clock runs from completion or termination of the PROJECT, not from your own last touch of the site. Going back in March to fix something does not restart a clock that started in November. Neither 'completion' nor 'termination' is defined in the statute, which is a reason to record early, not a reason to hope.
• Putting the gross invoice total on the notice. § 40-301.02(b)(3) requires the amount claimed 'less any credit for payments received up to and including the date of the notice of intent.' An inflated figure is not something a judge trims — it is non-compliance with subsection (b), and § 40-301.02(a)(1) makes a non-compliant notice VOID.
• Treating the nine content items as a checklist you can half-finish. There is no cure and no amendment in DC. A missing notarized perjury affidavit, a good-standing certificate that turned out to be 200 days old, a residential job with no written home improvement contract to attach — any one of them and the notice is void. The Recorder of Deeds accepting your filing at the counter proves nothing; the office records documents, it does not certify compliance.
• Mailing the 5-business-day copy and stopping when it comes back. § 40-301.02(a)(2) requires you to post a copy of the recorded notice on the property, visible from an entry point, if the certified mail is returned unclaimed or undelivered. The returned envelope is the trigger for the second step, not the end of the first.
• Recording and then sitting on service. If the GC hired you, every payment the owner makes to the GC before you serve the recorded notice discharges the lien and reduces what the property is chargeable for, dollar for dollar (§§ 40-303.03, 40-303.04). Delay between recording and service is not neutral — it is money out of your pocket.
• Filing suit on day 179 and thinking you are done. § 40-303.13(a)(1)(B) requires a notarized notice of pendency of action recorded within 10 days of filing, and § 40-303.13(a)(2) terminates the lien if you miss it. This is the most common way a DC claimant who did everything else right loses the lien anyway.
• Expecting to collect your full invoice. § 40-303.02(a) caps a first-tier claimant's lien at the amount due or to become due but unpaid to the original contractor, and reduces it further if the GC's breach cut down the GC's own recovery. Owed $200k on a job where the owner still owes the GC $40k? Your lien is worth $40k at best. Use § 40-303.05 to make the owner tell you the number — if they refuse or lie, the property becomes liable as if no payments had been made to the contractor.
• Filing a lien on a District or federal job. No mechanics lien attaches to District-owned or federally owned property, and DC has more of both than anywhere else in the country. The remedy is the payment bond: written notice to the prime within 90 days of your own last labor or material, stating the amount claimed with substantial accuracy and naming the party you worked for, and suit within one year of that same date (D.C. Code § 2-201.02; 40 U.S.C. § 3133(b)(2), (b)(4)). Time spent on a notice of intent here is time stolen from the only window that mattered.
• Assuming the owner cannot touch your lien. DC has no notice of contest and no demand-to-commence-suit, but the owner can pay the claim amount into court or post an undertaking with sureties and get the property released under §§ 40-303.16 and 40-303.17. Your deadlines do not pause when that happens — you still have 180 days from recording to sue and 10 days from filing to record the pendency notice.
• Signing a subcontract that forbids you from contacting the owner and believing it. Any clause in a contract, purchase order or similar document that prohibits a subcontractor, materialman or supplier from contacting the owner is VOID to the extent it stops you from giving the § 40-303.02(b) notice. Send the notice.
• Assuming an architect or engineer can lien in DC. It is not established. 'Project' in § 40-301.03(7) is defined in terms of erection, construction, improvement, repair or addition, and does not name design services; no DC authority establishing design-professional lien rights was located, and practitioner sources report the Recorder of Deeds reads the statute to require physical labor. Equipment rental is equally unsettled. Record protectively if you are inside 90 days, but get a lawyer's opinion before you spend money enforcing.

After you file

• Mail the owner a copy of the RECORDED notice by certified mail within 5 business days of recording, and if it comes back unclaimed or undelivered, post a copy on the property in a spot visible from an entry point (D.C. Code § 40-301.02(a)(2)). Claimants routinely stop at the returned envelope. The posting is not optional.
• If the general contractor hired you, serve the recorded notice on the owner separately — in person on the owner or their agent, or by posting if neither can be found — and do it immediately. Until you do, every payment the owner makes to the GC discharges your lien pro tanto (D.C. Code §§ 40-303.03, 40-303.04). After you do, the owner is bound to retain enough out of later payments to cover what the GC owes you.
• Keep sending refreshed written notices of the amount due to the owner as your balance grows. The § 40-303.02(b) protection only covers the amount you actually stated.
• Diary two dates the day you record: day 180 from the recording date (suit deadline) and, once you file, day 10 from the filing date (notice of pendency deadline). Missing either one terminates the lien under § 40-303.13(a)(2).
• When you sue, name the principal contractor as a defendant if you are not the principal contractor, and name everyone else who has recorded a lien on the property (D.C. Code § 40-303.08).
• Remember the ceiling. A first-tier claimant's lien is limited to the amount due or to become due but unpaid to the original contractor, and is cut down further if the GC's own recovery is reduced by the GC's breach (D.C. Code § 40-303.02(a)). Know that number before you spend money enforcing.
• When you are paid in full, enter satisfaction of the lien on demand and at the cost of the person asking. Refusing costs you a $50 forfeiture plus all damages the other side can prove (D.C. Code § 40-303.15).
• There is no fallback money judgment against the owner. § 40-303.19 bars a subcontractor, materialman or workman from a personal judgment against the owner unless the owner made a written promise, supported by consideration, to answer for the debt. If the lien fails, the property owner is not a target.