How to Invoice for Software Licenses and API Costs
Are you paying for your client's AWS or OpenAI bills? Learn how to professionally pass through software costs on your invoices.
Kartikeya Mishra
E-E-A-T Verified AI Engineer
If you are an AI Engineer, you likely use third-party APIs like OpenAI, Anthropic, or Pinecone. If you are paying for these out of pocket, you are losing money every second.
1. The 'Reimbursable' Strategy
Your contract should state: "Client is responsible for all third-party software and API licensing costs incurred during the project."
2. Invoicing the Markup
It is standard practice to add a 10-20% Administrative Markup when you pay for these services on behalf of the client. This covers the cost of you managing the billing and the currency exchange risks.
- API Cost: $100
- Admin Fee (15%): $15
- Total Line Item: $115
3. Transparency is Key
Always provide the original receipts as an attachment to your professional invoice.
🛑 Privacy Warning
Receipts often contain your personal credit card info or address. Use DocuFix.in to format and prepare your receipt attachments locally without uploading them to a random server.
Frequently Asked Questions (FAQ)
Should I put the client's credit card on the API account?
Yes. This is the best long-term solution. It ensures the service isn't cut off if you stop working together and keeps your invoicing clean.
What if I use my own 'Enterprise' license?
If you are providing access to a tool you already pay for, bill it as a "Seat License Fee" rather than a reimbursement.
How do I handle 'Usage-Based' billing?
Estimate the monthly cost in your proforma invoice and bill the actuals at the end of every month.