CIV-GP-11 – Affidavit of Service by Mail

Jurisdiction: Country: United States | Province or State: New York

What is a CIV-GP-11 – Affidavit of Service by Mail?

The CIV-GP-11 is an official Civil Court of the City of New York form. You use it to swear that you mailed legal papers in a case. It is a sworn statement, signed before a notary. It tells the court who you mailed, where you mailed, when you mailed, and what you mailed. The form is your proof that service by mail happened the right way.

You typically use this form after a lawsuit starts. You can also use it to prove the mailing part of substitute service when the law requires both delivery and mailing. In New York practice, many papers can be served by mail. The court needs proof of that service before it will act on your papers. The CIV-GP-11 supplies that proof.

Who uses this form?

Landlords and tenants in housing-related matters that are filed in the Civil Court’s General Civil Part. Small business owners are suing for unpaid invoices. Consumers and businesses defending claims. Self-represented litigants. Attorneys and their staff. Judgment creditors who must mail post-judgment papers. If you mailed papers to the other side or their lawyer, the person who did the mailing completes the CIV-GP-11.

You would need this form whenever a statute or court rule requires proof of service by mail. For example, you file a motion and serve it by first-class mail. You send discovery demands by mail. You mail a copy of the papers after serving by substitute service (deliver-and-mail or nail-and-mail). You mail post-judgment notices or demands when the law allows mail service. In each case, the court needs evidence that service was done right. The CIV-GP-11 is that evidence.

Typical usage scenarios

You mail your motion papers to the defendant’s attorney and need to prove it. You served a summons by substitute service and then mailed a copy as the law requires. You mailed a Notice to Admit to the other side. You mailed a notice of settlement or a proposed judgment. You served opposition papers by mail to meet a filing deadline. In each scenario, the form captures the essential facts of the mailing and backs your filing.

In short, the CIV-GP-11 is the Civil Court’s standard proof for service by mail. It lives in your court file as a sworn affidavit. The judge relies on it to decide whether your service was valid and timely.

When Would You Use a CIV-GP-11 – Affidavit of Service by Mail?

You would use this form whenever you chose or were required to serve papers by mail in a New York City Civil Court case. For most papers after a case starts, service by mail is allowed. If you mail those papers, you file a CIV-GP-11 from the person who did the mailing. The court reads it to confirm the date of service, the recipient, and the mailing details. That affects deadlines and whether the court will consider your papers.

As a tenant responding to a landlord’s motion, you might serve your opposition by mail. Your friend, who is not a party, drops the envelope at the post office. That friend then signs the CIV-GP-11. You file it with your opposition so the court knows you served on time.

As a landlord seeking discovery, you mail your document demands to the tenant’s attorney. Your office assistant, who is not a party, completes the CIV-GP-11. You attach it to any later motion to compel, so the judge sees you properly served the demands.

As a small business owner suing for nonpayment, you serve a Notice to Admit by mail. You then file the CIV-GP-11 to start the response clock. If the other side ignores it, you have proof you mailed it.

As a plaintiff who served the summons by substitute service, you also must mail a copy. You use the CIV-GP-11 to prove the mailing step. You then file your proofs of service within the set time. That allows the service to become complete and lets your case move forward.

As a judgment creditor, you may mail certain post-judgment papers when the law allows mail service. You use the CIV-GP-11 to prove those mailings. The court needs that proof before granting further relief.

You do not use this form to start a new case by mail alone. New York generally does not allow service of a summons by mail unless specific rules are followed. Some papers cannot be served by mail at all, such as subpoenas to witnesses. In those situations, the court or statute will specify personal service or another method. Use the CIV-GP-11 only when mail service is permitted for the paper you served.

Legal Characteristics of the CIV-GP-11 – Affidavit of Service by Mail

The CIV-GP-11 is a sworn affidavit. It is legally significant because the court treats it as evidence of service. You sign it before a notary. You declare the facts under oath. If the affidavit is false, you risk penalties for perjury. That makes it a serious, binding statement in your case file.

What gives the affidavit its force is proper execution and clear facts. The person who actually mailed the documents must sign it. The affidavit must identify the case, the recipient, the address used, the date of mailing, the place of mailing, and the papers mailed. It must state that the envelope was properly addressed and stamped, and placed in the U.S. mail. The notary must administer an oath and complete the notary block. When those requirements are met, the affidavit shows valid mail service.

Enforceability depends on compliance with service rules. In New York practice, many papers after a case starts can be served by first-class mail. Service is complete upon mailing. The recipient’s response time is extended by a set number of days for mail. Some papers have stricter requirements. For example, if you served a natural person by substitute service, the envelope for the mailing must be marked “personal and confidential.” The envelope must not show that it is from an attorney or related to a lawsuit. If the law requires certified mail, you must use certified mail and keep the receipts. The affidavit should reflect those details. The court then has a record that you followed the rule that applies.

The person serving by mail should be at least 18 and not a party to the case. In many post-commencement situations, a party may serve by mail. Still, using a non-party server avoids disputes and fits the form language. The key is that the signer swears to facts from personal knowledge of the mailing.

The court also looks at the filing. For mailed service of motion papers, you usually file the affidavit with your papers. If you used a substitute service to serve a summons, you must file proof of service within a set time. Service becomes complete only after proper filing. Late filing can delay or void service. The CIV-GP-11, together with any companion affidavits, meets those filing needs.

In short, the CIV-GP-11 works because it is a sworn, detailed record. It shows you used a permitted method, on the correct person, at the correct address, in the correct way. It ties the date of mailing to any deadlines. Courts rely on it to move your case forward or to enter default when appropriate.

How to Fill Out a CIV-GP-11 – Affidavit of Service by Mail

Follow these steps to complete the form correctly. You will avoid rejection and protect your deadlines.

Step 1: Gather what you need.

Have a full copy of the papers you mailed. Confirm the correct caption and index or docket number. Confirm the exact name and address of the person or attorney you served. Have the date and location of mailing. If you used certified mail, have the receipt number. Locate a notary public for signing.

Step 2: Confirm you are the proper signer.

The person who actually placed the envelope in the mail must sign the affidavit. That person should be at least 18 and not a party to the case. If you are a party and you mailed the papers, ask a non-party to remail and sign if the form requires a non-party server. The court expects the signer to have first-hand knowledge of the mailing.

Step 3: Complete the caption at the top.

Write “Civil Court of the City of New York” and the county, such as “County of Kings” or “County of New York.” Enter the index or docket number exactly as it appears on your papers. List the full names of the plaintiff(s) and defendant(s) in the same order as the case caption. Accuracy here matters, because the clerk files by these details.

Step 4: Identify the deponent (the person signing).

Print the server’s full legal name and address. State that the server is over 18 and not a party to the action. If the form has checkboxes or pre-printed language, follow it. The court wants to know who made the mailing and that the person is qualified.

Step 5: Describe what was mailed.

List each document by title and date. For example: “Notice of Motion dated March 1, 2025; Affirmation in Support with Exhibits A–C; Proposed Order.” If you mailed discovery, list: “Demand for Production of Documents dated March 1, 2025.” Be specific. The judge needs to see exactly what you served.

Step 6: State how you mailed.

Indicate that you enclosed true copies in a sealed envelope. State that you addressed the envelope properly, with first-class postage prepaid. State that you deposited the envelope in an official USPS depository. Include the date of mailing and the location, such as the post office branch or city and state.

If a rule required a special method, say so. For certified mail, include “by certified mail, return receipt requested” and the tracking number. If you mailed the “personal and confidential” envelope as part of substitute service on a natural person, say that you marked it “personal and confidential” and that the envelope did not show it came from an attorney or was related to a lawsuit.

Step 7: Identify each recipient and address.

State the full name and the role of each person served, such as “Attorney for Defendant.” Include the law firm name if served on counsel. Provide the street address, city, state, and ZIP code. Use the address designated for service if one has been provided. If multiple recipients were served, list each one. If no space remains, write “See Schedule A” and attach a continuation page with the full list.

Step 8: Add any timing details required by the rule.

If you served motion papers, consider deadlines. When service is by mail, service is complete upon mailing, but the opponent’s response time extends by mail days. If the form has a field for a return date or response date, complete it as your notice of motion shows. Make sure your mailing date meets any counting rules for the chosen return date.

Step 9: Review for accuracy and consistency.

Check that the date of mailing in the affidavit matches your proof of mailing, if any. Confirm that names and addresses match your envelope labels. Ensure the caption and index number match your filed papers. Confirm that the county is correct.

Step 10: Sign in front of a notary.

Do not sign until you are with a notary public. Show ID if asked. The notary will administer an oath. You will sign and date the affidavit. The notary will complete the jurat, including the date, county, and notary stamp. If the form has a pre-printed notary block, ensure it is filled in completely. A missing notary seal or date can cause rejection.

Step 11: Attach schedules and exhibits, if needed.

If you referred to “Schedule A” for extra recipients, attach it and label it clearly. If you used certified mail, attach copies of receipts or tracking pages as exhibits. If you served under a rule that required a particular envelope marking, you may attach a sample of the envelope face if you kept one. Keep originals of USPS receipts for your records.

Step 12: Make copies.

Make a copy of the signed, notarized affidavit for your file. If you must serve a copy of your proof of service on other parties, copy it for them as well. Keep your mailing receipts with your copy of the affidavit.

Step 13: File the affidavit properly.

File the original CIV-GP-11 with the court as required. If you are filing motion papers, include the affidavit in the motion packet. If your case uses an electronic filing system, upload the scanned affidavit in the correct document category. For service of a summons by substitute service, file the affidavits of service within the time set by law. Service becomes complete only after timely filing. If you served additional mailings for a default request, include the affidavit in your default judgment packet.

Step 14: Calendar deadlines.

Service by mail affects deadlines. Service is complete upon mailing for most post-commencement papers. The other side gets extra days to respond because you used mail. Count those days from the mailing date in your affidavit. Calendar your follow-up date based on those rules. If the court sets specific service deadlines in an order, follow that order.

Common pitfalls to avoid

Do not let a party sign this form if the form states the server is not a party. Use a non-party adult to mail and to sign. Do not leave out the county or the index number. Do not forget the notary. An unsigned or unnotarized affidavit has no value. Do not use a business name or law firm name on the envelope when mailing to a natural person as part of substitute service. Mark the envelope “personal and confidential” when required. Do not assume certified mail is always required; use it only when a statute or order requires it. If certified mail is required, do not skip the return receipt. Always mail to the correct address for service. Once an attorney appears, serve the attorney at the address of record, unless the court orders otherwise.

Real-world example: You filed a motion to dismiss. Your assistant, not a party, places the motion packet in the mail to the plaintiff’s attorney at the address on the caption. The assistant completes the CIV-GP-11 the same day, swearing to the date, location, and method of mailing. The affidavit lists the motion papers by title and date and names the attorney and firm, with the full address. The assistant signs before a notary. You file the motion with the CIV-GP-11 attached. The judge then knows you served by mail on the date shown and can calculate the opponent’s response due date.

Another example: You served the summons by delivery and mail. The process server delivered a copy to a person of suitable age and discretion at the defendant’s home. A second step required mailing a copy to the defendant at the same address. Your mailing clerk sent that copy in an envelope marked “personal and confidential,” with no law firm markings. The clerk completes the CIV-GP-11 to prove the mailing date and address. You file both the process server’s affidavit and the CIV-GP-11 within the filing window. Service then becomes complete under the rule.

If you follow these steps, your CIV-GP-11 will give the court what it needs. It will tie your mailing to the case, identify the exact papers served, and show proper method and timing. That is how you keep your filings on track in the Civil Court of the City of New York.

Legal Terms You Might Encounter

• An affidavit is a written statement of facts that you swear are true. On the CIV-GP-11, the person who mailed the papers signs the affidavit and swears to the mailing details. That person is the deponent, also called the affiant. The deponent must appear before a notary public to swear and sign.
• Service means delivering legal papers to another party in a way the rules allow. Service by mail means you put the papers in the mail to the recipient’s address. The CIV-GP-11 is proof that service by mail happened.
• The caption is the heading on your case documents. It lists the court, the parties’ names, and the case type. You will copy the caption onto the CIV-GP-11 so it matches your case exactly. The docket number, also called an index or case number, is your unique case ID. Put it on the form so the clerk can match your proof to the right case.
• The recipient is the person or business you are serving. The address of record is the mailing address used for that party or their attorney. You must use the correct address of record on the CIV-GP-11. If a party has an attorney, you usually mail it to the attorney.
• First-class mail is standard mail with a stamp or metered postage. Many filings use first-class mail for service. Certified mail adds tracking and a mailing receipt. Return receipt requested adds a green card or electronic proof of delivery. Some papers require certified or return receipt service. If you used those, the CIV-GP-11 should note it.
• Postage prepaid means you paid the full postage before mailing. The court will not accept service if the postage was underpaid. The form will ask you to confirm that postage was prepaid.
• The venue is the location listed at the top of the notary block. It shows the state and county where you swore to the affidavit. Sworn to before me means you signed in front of a notary, who then completed the notary section. The notary adds their signature, stamp, commission number, and expiration date.
• An envelope endorsement is any writing on the envelope that rules require. Some papers must state “Personal and Confidential” or include no law firm name. If you used any endorsement, state it on the CIV-GP-11.
• A proof of mailing is any receipt from the post office that shows you mailed the envelope. For first-class mail, this may be a stamped certificate of mailing. For certified mail, it is the receipt with the tracking number. Keep these with a copy of the CIV-GP-11. They support your affidavit if anyone later questions service.

FAQs

Do you need a notary to sign the CIV-GP-11?

Yes. The CIV-GP-11 is an affidavit. The person who mailed the papers must sign in front of a notary public. Do not sign before you meet the notary. Bring a valid ID and complete the form except for your signature.

Do you, as a party, fill out the CIV-GP-11?

The person who actually mailed the papers fills it out. That may be you or another adult, depending on the paper served. Many mailings can be done by a party. Some mailings must be done by a nonparty adult. Check the rules for the paper you served. If a nonparty must mail, have that person complete and notarize the CIV-GP-11.

Do you list every document you mail?

Yes. List each document by its full title. For example, “Notice of Motion,” “Affidavit in Support,” and “Exhibits A–C.” If the envelope held multiple items, include all of them. The affidavit should match your actual mailing.

Do you need certified mail or a return receipt?

Only if the rules for that paper require it. Many papers allow first-class mail. Others require certified mail, sometimes with a return receipt. Follow the rule for the specific paper you served. If you used certified mail, record the tracking number and keep the receipt.

Do you serve the party or the attorney?

If a party has an attorney, you usually mail to the attorney’s address. If a party does not have an attorney, you usually mail to the party’s address of record. Use the address on the most recent document filed. If the party gave a new address, use the updated address.

Do you file the CIV-GP-11 with the court?

In most cases, yes. You file the original notarized affidavit as proof that service occurred. File it with the court handling your case. Attach it to your filing if required. If the rules call for separate filing, submit it promptly. Keep a copy for your records.

Do you need to mail to more than one person?

You must mail to each party who must receive the paper. If several parties or attorneys appear in the case, mail to each one. Complete a separate CIV-GP-11 for each mailing, or list all recipients with full details. The safest practice is one affidavit per recipient.

Do you need the exact time of mailing?

Record the date and place of mailing. Time of mailing helps, but is not always required. If the form asks for time, include it. Always include the city, state, and the post office or mailbox used. Be precise and consistent with your proof of mailing.

Do you need to attach receipts to the CIV-GP-11?

You do not have to attach them to the affidavit unless a rule or judge requires it. Still, keep all receipts. Keep the postmarked certificate of mailing, certified mail receipt, or tracking printout. Store them with your copy of the CIV-GP-11.

What if your mail is returned as undeliverable?

Do not ignore it. Check the address you used. Confirm you mailed to the current address of record. If the address was wrong or outdated, correct it and re-serve as allowed. Prepare a new CIV-GP-11 for the new mailing. File the updated proof promptly.

Checklist: Before, During, and After the CIV-GP-11 – Affidavit of Service by Mail

Before signing

• Confirm you may serve the specific paper by mail. Some papers require personal delivery.
• Confirm who must mail it. Some papers can be mailed by a party. Others require a nonparty adult.
• Verify the recipient’s address of record. Use the most recent address in the case file.
• Check whether to serve the attorney instead of the party.
• Identify all recipients. Include each party who must get a copy.
• List every document enclosed. Match the document titles to the actual papers.
• Confirm the case caption and docket number. Copy them exactly from your case documents.
• Choose the correct mail class. Use first-class mail if allowed. Use a certified or return receipt if required.
• Prepare envelopes. Use correct names and addresses. Add any required envelope endorsements.
• Weigh envelopes or use a postal scale. Confirm full postage is prepaid.
• Decide your mailing location. Use a post office or a known USPS mailbox.
• Gather proof of mailing supplies. Bring funds for receipts, tracking, or a certificate of mailing.
• Print the CIV-GP-11. Fill in all known details except the signature and notary section.
• Bring government-issued ID for notarization.
• Give yourself time. Mail and notarize promptly to meet your filing timeline.

During signing

• Do not sign until you are before a notary public.
• Review the caption and docket number for accuracy.
• Confirm each recipient’s full name and address are correct.
• Confirm the mailing date, city, and state match your receipt.
• Confirm the mail class used. Note certified mail and tracking numbers if used.
• Confirm all documents mailed are listed by correct titles.
• Complete all fields, including your name, address, and contact details if requested.
• Swear or affirm the truth of your statements to the notary.
• Sign the affidavit in ink. Use your regular signature.
• Ensure the notary completes their block. Look for signature, stamp, commission number, and expiration date.
• Check the venue in the notary block. It should list the state and county where notarized.
• Review for blanks. Do not leave any required fields empty.
• Make a copy of the signed and notarized form for your records.

After signing

• Attach the CIV-GP-11 to your filing if needed, or submit it as a separate proof.
• File the original notarized affidavit with the court as required in your case.
• If your filing has a return date or hearing date, file proof of service promptly.
• Serve copies of the affidavit on other parties if required.
• Store your copy with your proof of mailing. Keep certified receipts and tracking results.
• Calendar any follow-up deadlines that depend on the service date.
• Track mail delivery status if you used tracking. Save a screenshot of the delivery confirmation.
• If the mail returns undelivered, re-check the address and re-serve as allowed. Prepare a new affidavit.

Common Mistakes to Avoid CIV-GP-11 – Affidavit of Service by Mail

Using the wrong address of record

• Don’t guess an address. Using an outdated or incorrect address can void service. That can delay your motion or response. Always verify the current address from the most recent filing or notice.

Letting the party that must not serve do the mailing

• Some papers must be mailed by a nonparty adult. If a party mails those papers, service may be invalid. The court may reject your proof and reset your deadlines. Confirm who may serve before you mail.

Leaving out documents from the list

• If the affidavit does not list everything enclosed, your proof is incomplete. A missing item can cause a defect in service. List each document by name. Match the contents of the envelope exactly.

Signing outside the notary’s presence

• Don’t sign early. If you sign before meeting the notary, the affidavit is defective. You may need to redo the service or refile the affidavit. Sign only when the notary instructs you.

Choosing the wrong mail class

• Some papers require certified mail or a return receipt. If you use standard mail when a different method is required, the service may be invalid. Confirm the allowed mail method before you send.

Omitting the case number or using the wrong caption

• A wrong caption or a missing docket number can cause filing issues. The clerk may not match your proof to the case. Double-check the caption and number before notarizing.

Missing the filing step

• Mailing the papers is not enough. You must file proof of service. If you forget, the court may not consider your filing. File the CIV-GP-11 promptly as your case timeline requires.

What to Do After Filling Out the Form CIV-GP-11 – Affidavit of Service by Mail

1. File the original notarized CIV-GP-11 with the court. If the rules say to attach it to your submission, do that. If the rules call for separate filing, submit it on its own. Either way, file promptly so the court has proof of service.
2. If your case has a hearing or return date, confirm your deadlines. Some deadlines are counted from the date of mailing. Others are counted from the date of filing. Record the dates on your calendar so you do not miss them.
3. If you served multiple parties, confirm that each one got a separate mailing. If you used certified mail, track each number. Print or save proof of delivery for each recipient. Keep these with your file.
4. If any mail is returned, check the reason. If the address is wrong or the forwarding time has expired, locate the current address of record. Re-mail as allowed. Complete a new CIV-GP-11 for the new mailing. File the updated proof promptly.
5. If you discover an error on the CIV-GP-11, fix it fast. If the error is minor, prepare a corrected affidavit and file it. If the error affects the service itself, re-serve the papers and complete a new affidavit. Do not rely on a flawed proof.
6. Serve a copy of the filed CIV-GP-11 on other parties if required. Some cases expect all filings to be shared. If sharing is required, mail or deliver copies and keep proof of that service.
7. Store your records. Keep a copy of the completed CIV-GP-11, any mailing receipts, and delivery confirmations. Keep them until your case is resolved and any appeal period ends. You may need them if service is challenged.
8. Monitor the case after filing. Watch for opposition papers or court notices that reference your service date. If deadlines run from the date you mailed, calculate response times accordingly. Stay ahead of the schedule.
9. If the court schedules a conference or hearing, bring your proof. Have copies of the CIV-GP-11 and mailing receipts ready. This helps if anyone questions the service or timing.
10. If you work with an assistant or process server, align your practice. Standardize envelopes, address checks, and receipt retention. Use one affidavit per recipient to avoid confusion. Consistency reduces errors across your filings.
11. Finally, update your service log. Note who you served, how you served, and when you filed proof. A simple log helps you track service across multiple recipients or motions. It also speeds up your next mailing.