Form 10A – Defendant’s Claim

Jurisdiction: Country: Canada | Province: Ontario

What is a Form 10A – Defendant’s Claim?

Form 10A is the document you use to make your own claim in an ongoing Small Claims Court case. You use it when you have been sued and you want money or property from the plaintiff. You can also use it to bring in another person or business who should share responsibility. In other words, it is the Small Claims Court version of a counterclaim or third-party claim.

You file Form 10A under the same court file as the main case. It lets you ask the court for a judgment in your favour. You can claim for money, the return of personal property, or both. Your claim must fit within the Small Claims Court’s monetary limit. If your loss is higher, you can choose to give up the excess to stay in this court.

You typically use this form if the plaintiff owes you money connected to the same dispute. You also use it if someone else caused or contributed to the plaintiff’s loss. In that case, you ask the court to make that person repay you if you are found liable. You can claim contribution, indemnity, or a full recovery.

This form is common in business, consumer, and property damage disputes. Here are practical examples. You are a contractor being sued for poor workmanship. You file a defendant’s claim against your subcontractor, who did the work. You run an auto shop, and a customer sues over a failed repair. You claim against the parts supplier under warranty. You are a retailer, and a customer sues for a defective product. You claim against the manufacturer. You are a homeowner sued by a neighbour for water damage. You claim against the roofer who caused the leak.

Who typically uses this form?

Defendants who want to protect their position and recover their own losses. That includes sole proprietors, corporations, landlords and tenants after a tenancy ends, contractors, trades, retailers, service providers, and everyday consumers. You do not need a lawyer to file. You can file it yourself or have a licensed representative file it for you.

You would need this form if you want the court to make orders in your favour in the same lawsuit. If you do not file it, you may lose the chance to raise your own claim in this case. You may also face a separate limitation period problem if you try to start a new claim later. Filing the defendant’s claim keeps all related issues in one courtroom. That saves time, avoids duplicate evidence, and supports a fair outcome.

When Would You Use a Form 10A – Defendant’s Claim?

You use a defendant’s claim when your claim grows out of the same events as the plaintiff’s claim. The connection matters. The court expects the facts to overlap. If your issue is unrelated, start a separate Small Claims Court claim instead.

Here are common situations. You provided services and the plaintiff did not pay the full amount. The plaintiff then sued you for alleged defects. You use Form 10A to claim the unpaid balance and to seek repayment from any subcontractor who caused the defect. You sold goods and the plaintiff sues for a refund. You claim your restocking fee and delivery charges under the contract. You were in a minor car collision and got sued for property damage. You claim your own repair costs based on the same incident. You are a landlord sued over damage to a unit after the tenancy ended. You claim for unpaid repairs supported by invoices. You are a tenant sued for rent after the tenancy ended. You claim the landlord kept your deposit without basis and failed to mitigate.

Typical users include business owners, trades, professionals, retailers, auto shops, homeowners, tenants, and landlords. Insurers sometimes file on behalf of insured defendants where subrogation or indemnity applies. You can also use the form to bring in a new party. For example, a supplier who agreed to indemnify you. Or a joint wrongdoer who should share fault.

Timing matters. You should act promptly after you are served with the plaintiff’s claim. In Small Claims Court, the usual practice is to file your defendant’s claim soon after you file your defence. If you wait too long, you may need permission from the court to proceed. Claims for contribution and indemnity also have a specific limitation clock. That clock often starts when you are served with the plaintiff’s claim. Do not delay.

Also consider the court’s monetary cap. If your claim is over the limit, decide whether to abandon the excess. If you do not want to abandon it, you must start a separate claim in a higher court. That may not be efficient. Many defendants choose to keep the combined dispute in Small Claims Court for speed and cost reasons.

Legal Characteristics of the Form 10A – Defendant’s Claim

A defendant’s claim is a formal pleading in an existing court case. Once the clerk issues it and you serve it, it becomes part of the lawsuit. It is legally binding because it invokes the court’s authority. The court can grant judgment on it if you prove your case or if the other side fails to respond.

Enforceability depends on proper process. You must file the form at the correct court location for the original case. You must pay the filing fee. The clerk will assign or confirm the court file number and stamp the claim. You must then serve the issued claim on every person or business you are suing. If you add a new party, you must serve that party as well. After service, you must file proof of service with the court. If you skip these steps, the court cannot deal with your claim.

The person or business you sue must deliver a defence to your claim within the set time. The usual period is 20 days after service, subject to delivery method and location. If no defence is delivered, you may ask the court for default judgment on your defendant’s claim. If a defence is delivered, your claim proceeds through the same case management track as the main action. The court will usually schedule a settlement conference that covers all claims in the file.

Your pleading must set out the material facts. State what happened, when it happened, and what you want. Do not argue the law in the form. Focus on the facts that prove your right to recover. Attach key documents that support your claim. Contracts, invoices, emails, photos, and estimates help. Clear attachments improve credibility and reduce disputes about basic facts.

Your claim must fit within Small Claims Court jurisdiction. That includes the monetary limit, the type of relief, and the parties. You can claim money or the return of personal property. You cannot seek remedies that only a higher court can grant. If you want interest, state whether you rely on a contract rate or the court’s default rate. If you want costs, claim your filing and service fees and other allowed expenses. The court may award modest legal costs if you used a licensed representative.

Be careful when adding new parties. Use exact legal names. For corporations, include the full registered name. If you sue a trade name, identify the legal entity behind it. Serving the wrong name can derail the case. Make sure you have the correct address for service. If you sue a person under a disability, special representation rules apply. Get advice if that issue arises.

Finally, consider settlement. Filing a defendant’s claim can shift negotiations. It shows you intend to recover your losses. It also creates risk on both sides. The court expects you to try to resolve disputes early. A well-pled defendant’s claim can move the file toward a practical settlement.

How to Fill Out a Form 10A – Defendant’s Claim

Follow these steps to complete, file, and serve your defendant’s claim accurately.

1) Confirm that a defendant’s claim is right for you.

• Make sure your claim connects to the plaintiff’s claim. The facts should overlap.
• Decide whom to sue. You can sue the plaintiff, a new party, or both.
• Check the amount. Keep it within the Small Claims limit or abandon the excess.

2) Gather your evidence.

• Collect contracts, quotes, work orders, and purchase orders.
• Pull invoices, receipts, statements of account, and payment records.
• Save emails, texts, photos, and expert estimates.
• Prepare a simple timeline of key dates and events.

3) Use the correct court location and file number.

• Use the same courthouse as the main case.
• Write the exact court file number from the plaintiff’s claim.
• Keep party names consistent with the main action.

4) Complete the court heading.

• Insert the court name: Superior Court of Justice – Small Claims Court.
• Insert the court address matching the existing file.
• Insert the existing court file number.

5) Identify the parties.

• List the plaintiff(s) and defendant(s) exactly as shown in the main action.
• Add any new party you are suing. Use the legal name and full address.
• For businesses, state if it is a corporation, partnership, or sole proprietorship.
• Provide phone and email for service if available.

6) State who is making this claim.

• Confirm you are the defendant filing the defendant’s claim.
• If more than one defendant is filing, list each one.
• If a representative signs, state their role and licence type if applicable.

7) Describe what you are claiming.

• Choose money, return of personal property, or both.
• State the total amount claimed. Include a clear breakdown.
• List principal, interest claimed to date (if any), and court costs to date.
• If you want property returned, describe it and give an estimated value.

8) Set out your factual story in plain language.

• Use short, dated paragraphs. Keep one fact per sentence.
• Start with the agreement or event. Then explain what went wrong.
• Link your loss to the plaintiff’s conduct or to a new party’s conduct.
• If you claim indemnity, say why. Quote or attach any indemnity clause.
• If fault is shared, explain each party’s role.

Example structure:

• On March 5, you hired me to install countertops.
• The contract price was $4,800 plus HST.
• You supplied the stone through XYZ Stone Ltd.
• The stone arrived chipped. I reported the defect the same day.
• You told me to install the stone anyway.
• You later refused to pay, claiming defects.
• I repaired your wall damage caused by XYZ’s delivery team.
• I suffered $2,100 in extra labour and materials.

9) Explain your legal basis in simple terms.

• For unpaid accounts, say you provided goods or services and were not paid.
• For damages, say the other party breached a duty and caused your loss.
• For contribution or indemnity, say the other party should repay you if liable.
• You do not need case law. Stick to facts that fit these bases.

10) Attach and label your documents as schedules.

• Number each schedule. For example, Schedule A: Contract dated May 1.
• Refer to each schedule in your facts. For example, “See Schedule A.”
• Include only readable copies. Highlight key terms if helpful.
• Keep the bundle tight. The court prefers concise, relevant exhibits.

11) Claim interest and costs.

• If you have a contract rate, state the rate and start date.
• If not, ask for pre-judgment interest at the court rate from a fair start date.
• Ask for post-judgment interest at the court rate.
• Claim your filing fee, service costs, and reasonable disbursements.

12) Provide any payment set-off or credits.

• Deduct payments received and credits given.
• Show your math to the final figure.
• If you hold a deposit, say how you applied it.

13) Review names, amounts, and dates for accuracy.

• Check spelling of all parties.
• Confirm addresses for service.
• Recalculate totals. Ensure the number in your prayer matches your breakdown.

14) Complete the signature block.

• Print your name and sign. Add the date.
• Include your address, phone, and email.
• If a lawyer or paralegal signs, include licence number and firm details.
• If a non-licenced agent signs, ensure you have authority to represent.

15) File the claim with the court.

• File online or at the courthouse for the existing file.
• Pay the filing fee. Keep your receipt.
• Ask the clerk to issue the claim. You will receive a stamped copy.

16) Serve every party you are suing.

• Serve the plaintiff(s) and any new party you added.
• Use an approved service method for each party type.
• For individuals, personal service or another permitted method works.
• For corporations, serve at the registered office or on an authorized person.
• Keep a record of how and when you served each party.

17) Prepare and file your affidavit of service.

• Use the court’s service affidavit form.
• Attach any delivery receipts or acknowledgments.
• File the affidavit promptly after service.

18) Calendar response deadlines.

• Mark 20 days from service for each defendant’s defence deadline.
• Add follow-up dates for potential default steps.

19) If no defence is delivered, consider a default judgment.

• Confirm proper service and the expired deadline.
• Prepare your default request. Include proof of the amount claimed.
• If your claim includes unliquidated damages, be ready to prove them.

20) If a defence is delivered, prepare for the settlement conference.

• Organize your documents. Create a slim, indexed package.
• Prepare a short summary of issues and your settlement position.
• Bring repair estimates and invoices to support your numbers.
• Be ready to discuss both the main claim and your defendant’s claim.

21) Keep communications professional and focused.

• Continue to exchange documents promptly.
• Consider settlement offers. Use your defendant’s claim as leverage.
• Confirm any deals in writing. Ask to put them on the court record if appropriate.

22) Maintain a clean file.

• Keep copies of all versions of your claim and exhibits.
• Keep proof of filing, service, and receipts for fees.
• Track your time and costs for a potential costs award.

Practical tips:

• Use plain language. Avoid arguments and adjectives.
• Put numbers in a simple table in an attached schedule if helpful.
• Do not attach your entire email archive. Include only key messages.
• Do not overreach. Claim what you can prove.
• If you add a new party, make service your priority. Delayed service can stall your case.

Quality checks before filing:

• Does your claim relate to the same events as the main case?
• Is your total within the court’s monetary cap?
• Are all parties named correctly with service addresses?
• Are your attachments clear and labeled?
• Have you claimed interest and costs correctly?

Filing a strong defendant’s claim protects your position. It lets the court resolve all connected issues in one proceeding. If you follow the steps above, you present a clear, supported claim. That improves your chances of a fair result and practical settlement.

Legal Terms You Might Encounter

Defendant’s Claim means your claim as a defendant against the plaintiff, another defendant, or a new party. You use this form to ask the court to order money, goods, or services in your favour arising from the dispute in the main claim. If you want the court to award you money, you need a Defendant’s Claim. A defence alone does not get you a money order.

Set-off is a defence that reduces what you might owe the plaintiff by what the plaintiff owes you. If you only want to reduce their claim, you can raise set-off in your defence. If you want the court to order the plaintiff or another party to pay you, file a Defendant’s Claim.

Contribution and indemnity is a type of Defendant’s Claim where you say another party should pay part or all of any amount you might owe the plaintiff. You use this when you believe someone else is responsible for the loss or should reimburse you if you lose the main claim.

Third party refers to someone not already named in the main claim who you bring into the case through your Defendant’s Claim. You name them if you want contribution, indemnity, or another remedy connected to the same events. You must serve them with your Defendant’s Claim and give proper notice.

Cause of action is the legal basis for your claim. It describes why the other party is liable to you. In this form, you explain your cause of action with clear facts. For example, breach of contract, negligent work, or unpaid invoices tied to the same transaction as the main claim.

Damages are the losses you ask the court to award. They can include direct losses, repair costs, or other amounts you can quantify. In the form, list each type of damage and the dollar amount. Attach documents that help prove the loss.

Interest and costs are amounts you may claim on top of damages. Interest compensates for the time your money was unpaid. Costs can cover certain filing and service fees, and a portion of your time or representation. In this form, state if you want interest and costs, and on what basis.

Service is the formal process of delivering court documents to the other parties. It ensures they know about your Defendant’s Claim. You must follow the rules for service, use a permitted method, and keep proof of service. The court may not deal with your claim if you do not serve it properly.

Limitation period is the deadline to start a claim. Your Defendant’s Claim must be within the allowed time or qualify for an exception. If you are close to a deadline, act quickly. Late claims can be dismissed even if you have strong facts.

Joint and several liability means more than one person can be responsible for the same loss. If you claim against multiple parties, the court may find each liable for all or part of the amount. In your form, explain each party’s role and how their actions caused your loss.

A settlement conference is a required step where a judge helps the parties discuss settlement and narrow issues. Your Defendant’s Claim will be on the table at this meeting. Use the form to present a clear, supported position so you negotiate from strength.

FAQs

Do you need to file a defence if you file a Defendant’s Claim?

Yes. A Defendant’s Claim does not replace your defence to the main claim. Your defence answers the plaintiff’s allegations. Your Defendant’s Claim asks for your own remedy. File both if you want to dispute the claim and also seek money or other relief.

Do you have to connect your Defendant’s Claim to the same events as the main claim?

Yes. Your claim should arise from the same transaction, occurrence, or facts. Or it should seek contribution or indemnity related to the main claim. If your claim is unrelated, start a separate small claim instead of using this form.

Do you file the Defendant’s Claim at the same court location as the main claim?

Yes. File at the same Small Claims Court location where the plaintiff started the case. This keeps all claims together under one court file for scheduling and settlement.

Do you have to serve every party named in your Defendant’s Claim?

Yes. Serve each person or business you are suing, including the plaintiff and any new parties. Use a permitted method and keep proof of service. Without proper service, the court may not hear your claim or may set aside any order you get.

Do you need to attach evidence to your Defendant’s Claim?

Attach key documents you rely on, such as contracts, invoices, emails, delivery records, or photos. Label them and refer to them in your facts. The goal is clarity. You can provide more evidence later, but early attachments help the court and the other side understand your case.

Can you amend your Defendant’s Claim if you find an error?

Usually yes. You can correct names, amounts, or facts and then serve the updated claim. If the case has moved forward, you may need the court’s permission. Act fast. The closer you get to hearing, the harder amendments become.

What happens to your Defendant’s Claim if the main claim settles or is dismissed?

It depends. If your claim stands on its own (for example, you say the plaintiff owes you money), it can continue. If your claim is only for contribution or indemnity, it may end if there is nothing left to contribute to. Tell the court how you want to proceed.

Do you need a representative to file a Defendant’s Claim?

No. You can file on your own. A representative can help if you want one. If a business files, ensure the person signing has authority. Always provide a current address for service and contact details so you receive court notices.

Checklist: Before, During, and After

Before signing – Court file details:

• The main claim court file number.
• The correct court location for the main claim.
• Parties:
• Exact legal names of all parties you are suing.
• Correct spellings and roles (plaintiff, defendant, new party).
• Business names and legal entities (corporation, partnership, sole proprietorship).
• Registered business names and any operating names.
• Facts and legal basis:
• A short timeline of events tied to the main claim.
• Clear cause of action (breach of contract, negligence, unpaid account).
• How each party you sue is responsible.
• Amounts:
• A damages table with subtotals and a total.
• Interest details (rate basis, start date if applicable).
• Any specific property or services you want delivered.
• Evidence:
• Key documents to attach (contracts, invoices, photos, emails).
• Legible copies, labeled and organized.
• Witness names and what they can confirm (for your planning).
• Deadlines:
• Limitation period status for your claim.
• Internal deadlines to file and serve.
• Authority and capacity:
• If filing for a business, proof you can sign.
• If suing on behalf of someone else, confirm legal authority.
• Practical items:
• Enough copies for filing and service.
• A plan and method for service.
• Payment method for filing fees.

During signing – Parties and roles:

• Verify every party you sue is listed correctly.
• Confirm addresses for service are complete and current.
• Claims and amounts:
• Check that each remedy requested is stated clearly.
• Confirm each amount matches your evidence and the totals add up.
• Facts:
• Ensure facts are in plain language, in date order, and tied to your claim.
• Remove speculation and keep to what you can prove.
• Attachments:
• Label each document you attach and refer to it in the facts.
• Make sure all pages are readable and complete.
• Limits and scope:
• Confirm the claim fits within Small Claims Court limits.
• Ensure the claim relates to the main dispute or seeks contribution/indemnity.
• Form details:
• Court location and file number are correct.
• Your contact information is accurate.
• Signature and date are present and legible.
• Consistency:
• Your Defendant’s Claim aligns with your defence strategy.
• If claiming set-off only, confirm it appears in your defence.

After signing – Filing:

• • File the original Defendant’s Claim with the same court location.
  • Pay the filing fee.
  • Ask the clerk to endorse copies for service.
  • Service:
  • Serve each party you are suing by an allowed method.
  • Note who served which documents, when, and how.
  • Prepare proof of service for each party served.
  • Court record:
  • File proof of service with the court promptly.
  • Check the court record for any returned mail or notices.
  • Scheduling:
  • Calendar all next steps and deadlines.
  • Watch for the defence to your Defendant’s Claim, if any.
  • Prepare for the settlement conference.
  • File management:
  • Keep a complete copy of everything filed and served.
  • Store originals of key evidence safely.
  • Maintain a contact log of communications with other parties.
  • Strategy:
  • Review settlement options and offers.
  • Update your evidence list and witness plan.
  • Consider whether amendments are needed and, if so, act early.

Common Mistakes to Avoid

Missing the connection to the main dispute

• Mistake: Filing a Defendant’s Claim about a separate, unrelated matter.
• Consequence: The court can strike your claim. You lose time and fees.
• Tip: Tie every fact to the events raised in the main claim or to contribution/indemnity.

Suing the wrong legal entity

• Mistake: Naming a trade name or individual when a corporation is responsible, or vice versa.
• Consequence: You may get a judgment you cannot enforce.
• Tip: Verify the exact legal name and capacity before you file. Don’t guess.

Leaving out proof of service

• Mistake: Serving the Defendant’s Claim but not filing proof of service.
• Consequence: The court may not schedule your matter. Orders can be set aside.
• Tip: Don’t forget to file proof of service for each party and keep copies.

Overstating or miscalculating amounts

• Mistake: Claiming amounts you cannot justify or totals that do not add up.
• Consequence: You lose credibility. The court may award less or dismiss parts.
• Tip: Use documents to support each dollar. Double-check your math.

Relying on conclusions instead of facts

• Mistake: Writing “They acted in bad faith” without facts that show what happened.
• Consequence: The court may disregard unsupported claims.
• Tip: Describe who did what, when, where, and how. Attach proof where possible.

Waiting too long to amend

• • Mistake: Spotting errors but delaying corrections.
  • Consequence: Amendments may require permission or be refused.
  • Tip: Fix errors early, then re-serve if needed. Act before key milestones.

What to Do After Filling Out the Form

File the claim with the correct court location

• Use the same Small Claims Court location as the main claim.
• Bring the original and enough copies. Ask the clerk to endorse copies.
• Pay the filing fee. Keep your receipt with your file copy.

Serve every party you are suing

• Serve the plaintiff if you claim against them. Serve any new parties you add.
• Use a permitted service method for each type of party.
• Track dates and details of service. Keep names of the person who served.

File proof of service

• Complete proof of service for each party.
• File it promptly so the court can move the case forward.
• Keep stamped copies for your records.

Wait for and review responses

• Parties you sued may file a defence to your Defendant’s Claim.
• Read any defence carefully. Note deadlines to reply or deliver documents.
• Adjust your strategy and evidence plan based on their position.

Prepare for the settlement conference

• Organize your facts, documents, and a clear summary of your claim.
• Be ready to explain your numbers and how you calculated them.
• Consider realistic settlement options. Prepare to discuss offers.

Exchange documents

• Share relevant documents with the other side on time.
• Keep a list of documents you sent and received.
• Bring organized copies to the settlement conference and any hearing.

Consider amendments or adding parties if needed

• If you learn new facts that change your claim, amend as early as possible.
• If another party is responsible, consider adding them. Assess deadlines.
• Serve amended documents and file proof of service again.

Monitor the main claim’s status

• If the plaintiff discontinues or the court dismisses the main claim, reassess yours.
• Decide whether to continue, narrow, or discontinue your Defendant’s Claim.
• Inform the court and the other parties of any change in scope.

Attend court events

• Appear at the settlement conference and any hearings.
• Bring your documents, proof of service, and a concise case summary.
• Take notes of any orders or deadlines the judge sets.

Follow through after resolution

• If you settle, put the agreement in writing. File necessary notices.
• If you obtain judgment, plan enforcement steps within the rules.
• If you discontinue your claim, file notice and serve it on the other parties.

Maintain your file

• Keep a clean, chronological file of all documents and notes.
• Store original evidence safely.
• Update your calendar with every deadline and event.