They owe you money. I make them pay.
You did the work. You sent the invoices. They are not paying. I draft a demand letter and send it via USPS certified mail with signature requested. $2,500 minimum for the Demand Package; most invoices get paid within 2 weeks.
Ask my AI Legal Analyst about your unpaid invoice
Tell me about the debt and I will scope the right step: the $2,500 Demand Package, or the $3,000 Written Negotiation Phase if the back-and-forth continues. A full review of your contract and invoices is the $300 Written Attorney Consultation, not this chat. AI-generated legal information, not legal advice.
One attorney letter on firm letterhead, USPS certified mail (signature requested) plus email, up to two client revision rounds before sending, review of the debtor's first substantive response with a short next-step recommendation, and a narrow counter-response if strategically appropriate. Multi-round negotiation is the $3,000 Written Negotiation Phase. Rush 48-hour turnaround is available for +$150.
The attorney demand on my letterhead, with the supporting chronology, damages calculation and exhibits, with first-response review. For a California or Washington matter, where I determine it is legally and strategically warranted, I include one draft complaint or arbitration demand for one dispute, expressly marked DRAFT - NOT FILED, within the agreed package fee. Filing, filing fees, service of process, appearances and conducting any court or arbitration proceeding are not included; any pleading or other proceeding paper beyond the one included draft is separately scoped. Up to two revision rounds; first-response review included. Best for larger balances and sophisticated counterparties.
A written contract helps but is not required. Emails confirming scope, approved deliverables, invoices the client acknowledged, or proof they used your work can support the letter. Send the invoice, any contract or purchase order, proof of delivery, and prior correspondence. The stronger the documentation, the stronger the leverage.
A demand letter is a pre-litigation communication, not a court filing, so I can send these for debtors nationwide using the governing law in your agreement (or conflict-of-laws principles if there is no choice-of-law clause). Filing a complaint or appearing as counsel of record requires bar admission in the relevant state; for California matters I handle the full pre-litigation cycle directly.
The economics of the $2,500-minimum demand package work best for invoices above roughly $2,000. Below that, small claims court may be the better path unless the principle matters more than the money. If you just want an attorney to review the file and tell you the best route and the leverage you actually have, the $300 Written Attorney Consultation is the lower-cost option (written response within two business days; not a full demand letter).
What you get for $2,500 minimum
Everything needed to maximize your chances of getting paid.
Unpaid Invoice Demand Letter
- Attorney-drafted demand letter on legal letterhead
- Legal research on your contract and applicable state law
- Itemized damages calculation with interest and late fees
- Draft lawsuit attached as exhibit showing you are ready to file
- USPS certified mail (signature requested) + email to the other side
- Citations to applicable late-fee and statutory interest provisions
- 30-day payment deadline with clear escalation consequences
- Up to two client revision rounds before sending, plus review of the first response with a short next-step recommendation
Rush available: +$150 for 48-hour turnaround.
Illustrative examples: what a demand letter can accomplish
These are illustrative scenarios based on common fact patterns, not actual client matters.
Illustrative examples, not actual client results. Every matter depends on its own facts.
Developer completed 3-month project
Developer completed a 3-month project. Client approved all deliverables then stopped responding to invoices. I cited breach of the SOW and applicable state prompt payment statutes. Client paid $17,200 within 8 days.
Agency delivered 6-month campaign
Agency delivered a 6-month campaign. Client disputed scope after receiving final deliverables. I attached the signed MSA showing approved deliverables and calculated contractual late fees. Full payment received in 14 days.
Framing work on commercial project
Subcontractor completed framing work on a commercial project. GC withheld payment claiming deficiencies without documentation. I cited mechanics lien rights and prompt payment act violations. GC paid in full within 10 days.
IT consultant completed 2-week engagement
IT consultant completed a 2-week engagement. Client claimed dissatisfaction after using the deliverables for 3 months. I cited acceptance by conduct and contract payment terms. Settled for $7,800 in 12 days.
Why invoices go unpaid
I have seen every excuse. These are the most common reasons clients stop paying, and how my demand letters address them.
What makes my demand letters effective
An attorney's letter is different from your email. Here is what I include that changes the conversation.
How it works
Send me the details
Email the invoices, contract (if any), and a summary of what happened. Include any correspondence showing the client accepted or approved the work.
I confirm scope
I reply with any questions I have and confirm the fee and timeline. No work starts until you approve.
I draft the demand letter
I cite your contract, calculate damages with interest and late fees, and set a clear deadline.
USPS certified mail to the other side
I send the demand letter via USPS certified mail with signature requested, plus email if available. Most invoices get paid within 2 weeks once they see an attorney is involved.
Stop waiting for them to pay. An attorney's letter with a lawsuit attached changes the conversation.
Send me the details and I will confirm the fee and timeline.
Start My Demand Letter →Example scenarios: what a demand letter can do
Illustrative examples, not actual client results. Every matter depends on its own facts. Client reviews: 700+ on Upwork.
Example scenario: a client owes $15,000 and has not responded for 2 months. A demand letter on attorney letterhead leads to payment within 6 days.
Example scenario: an agency is owed $28,000 for completed work. A demand letter that calculates late fees under the MSA leads to full payment, late fees included, within 2 weeks.
Example scenario: three overdue invoices total $9,200. One demand letter covering all three leads to an $8,800 settlement in 10 days.
Frequently asked questions
Do I need a written contract?
A written contract is helpful but not required. If you have emails confirming the scope of work, approved deliverables, or invoices the client acknowledged, I can work with that. Even purely verbal agreements can support a demand letter if there is evidence of acceptance and use of your work product. The stronger the documentation, the stronger the leverage.
What if they dispute the quality?
If the client accepted the deliverables, used them, or asked for revisions without raising quality concerns at the time, that is evidence of acceptance by conduct. I cite this in the demand letter along with any approval emails, completion confirmations, or the client's continued use of your work. Retroactive quality disputes are rarely successful defenses to payment.
How much interest can I claim?
Interest rates depend on your contract and state law. If your contract specifies a late-payment interest rate, I calculate it per those terms. If not, I apply your state's statutory judgment interest rate or prompt payment act provisions. In many states, this is 7-10% annually. If your contract includes late fees, I calculate and include those as well.
What if they are in another state?
I draft demand letters for clients and debtors nationwide. The demand letter cites applicable contract terms and the governing law specified in your agreement. If there is no choice-of-law clause, I apply conflict-of-laws principles. The goal is to establish the debt and create leverage regardless of where the parties are located.
What if the amount is small?
The economics of a demand letter work best for invoices above approximately $2,000. Below that threshold, the $2,500-minimum fee may not be cost-effective unless the principle matters more than the money. For very small claims, small claims court may be a better option. I can advise on the best path forward based on your specific situation.
What happens if they still don't pay?
If they do not pay after the 30-day deadline in the demand letter, you have several options: file the lawsuit I drafted and attached to the demand, use small claims court if the amount qualifies, hire me to file and litigate the case, or use a collections agency. The demand letter with attached lawsuit establishes a clear record of your attempt to resolve the matter before litigation.
Related attorney services
Sergei Tokmakov is a California attorney, State Bar of California No. 279869, licensed since 2011. He prepares demand letters and supporting demand materials for California matters. The standard Demand Package is $2,500 for matters within the posted scope. Larger, multi-party, and unusually complex disputes are scoped separately. A written consultation addressing one defined legal question is $300.
- Demand Package: $2,500
- Commercial Dispute Action Package: $3,000
- Written consultation on one defined legal question: $300
This page provides general information, not legal advice, and does not create an attorney-client relationship. Each engagement requires a conflict check and written confirmation of scope.