Project Invoice Template: Billing for Project-Based Work
Project billing is different from hourly billing. When you're working for a fixed fee, your invoice needs to reflect deliverables — not hours. This guide covers project invoice structure, milestone billing strategies, and how to handle the dreaded scope creep.
Project billing vs hourly billing
The billing method you choose shapes your entire invoice structure:
| Billing type | How it works | Invoice shows | Best for |
|---|---|---|---|
| Fixed project fee | Agreed price for defined deliverables | Project name, deliverables, total fee, milestone being billed | Clear-scope projects (design, development, copywriting) |
| Hourly (time & materials) | Bill for hours worked, materials purchased | Hours × rate + itemized materials | Ongoing or undefined-scope work |
| Hybrid | Fixed fee + hourly rate for changes | Fixed fee + change orders billed separately | Projects where scope might evolve |
| Milestone billing | Fixed fee split across project phases | Which milestone, % of total, deliverables completed | Long projects, new clients, large budgets |
How to structure project invoices
Single invoice on completion
💡 Never do this with a new client. If they disappear after delivery, you have no recourse.
50/50 split
💡 Simple and widely accepted. Clear milestone: final delivery.
30/30/40 split
💡 Define 'midpoint' clearly in the contract — approved design, working prototype, etc.
Monthly progress billing
💡 Invoice on the 1st of each month for work done the previous month.
What to include in a project invoice
A project invoice differs from a standard hourly invoice. Here's what to include:
Project name & reference number
Links this invoice to the contract and statement of work
Project: Brand Identity Redesign — Project Ref: BRAND-2026-01
Milestone / phase being billed
Tells the client exactly what stage this invoice covers
Milestone 2: Initial design concepts delivered and approved
Deliverables completed at this stage
Proves value was delivered before payment is due
3 brand concept options, color palette, typography selection
Total project value
Context — shows this invoice is part of a larger agreement
Total project value: €6,000 (this invoice: €2,000 — 33%)
Amount billed to date
Running total of what has been invoiced so far
Previously invoiced: €2,000 (deposit). Today: €2,000. Remaining: €2,000.
Amount due now
Clear, unambiguous — the number the client needs to pay
Due now: €2,000 — due within 14 days
Free project invoice template
Use Chaser's free invoice builder to create a professional project invoice in minutes. Add project name, milestones as line items, and total project value — download as PDF instantly. No account required.
Create Project Invoice Free →Free. No signup. Instant PDF download.
Change orders and scope creep on invoices
Scope creep is the silent killer of project profitability. The fix: document every change with a change order, and invoice for it separately.
How to invoice for out-of-scope work
- 1.When a client requests work outside the agreed scope, pause immediately. Do not start the work until you have written agreement on cost.
- 2.Send a change order email: "This falls outside our original scope. I can complete this for €[X]. Should I proceed?"
- 3.Once approved (get it in writing — email is fine), complete the work and invoice with a separate change order invoice.
Change order invoice template
Change Order #1 — [Original Project Name] Reference invoice: INV-001 Description: [Detailed description of additional work] Reason: Out-of-scope request dated [date], approved by [client name] via email Change order fee: €[amount] (Rate: €[hourly rate]/hr × [hours] hrs) Payment due: [date — same terms as original contract]
Invoice sent. Now make sure it gets paid.
Chaser automatically follows up on unpaid project invoices — four escalating emails until the client pays. You focus on the work. We handle the chasing.
Start Free — Automate Your Invoice Follow-UpFrequently Asked Questions
What is a project invoice?
A project invoice is a billing document for fixed-price or milestone-based work — as opposed to hourly invoicing where you bill for time spent. A project invoice specifies which deliverables or milestones are being billed, the total project value, and what amount is due at this stage.
Should I invoice before or after completing a project?
For most projects, neither extreme works well. Best practice is milestone billing: invoice a deposit upfront (25–50%), invoice at a defined midpoint, and invoice the remainder on completion. This protects your cash flow and gives the client confidence that you're delivering before final payment.
How do I invoice for project changes (scope creep)?
Issue a separate change order invoice for any work outside the original scope. Reference the original project invoice number, describe the additional work, and list the cost. Your original contract should already specify that out-of-scope work is billable at your hourly rate. Never absorb scope creep silently — document and bill every change.
What split should I use for milestone invoicing?
Common splits: 50/50 (deposit + completion), 30/30/40 (start/midpoint/completion), 25/25/25/25 for long projects. The right split depends on project length and client trust level. For new clients or large projects, always get at least 30–50% upfront.
What should a project invoice number look like?
Use a sequential numbering system: INV-001, INV-002, etc. For milestone invoices on the same project, some freelancers use INV-001a, INV-001b, INV-001c to group them. What matters most is consistency — pick a format and stick with it. This is legally required in most countries.
Can I use Chaser for project billing?
Yes. Chaser's invoice builder works perfectly for project invoices — you can set milestones as line items, specify the total project value, and note what percentage is being billed at each stage. Chaser then automates follow-up emails if the invoice is not paid on time.