How to Invoice for Hourly Work (With a Simple Timesheet Format)

Hourly invoices get questioned more than fixed-price ones. Not because clients distrust you, but because a single line like "Design work — 37 hours" leaves them wondering what those hours were. Questions mean delays. A clear hourly invoice answers them before they're asked.

What an hourly invoice needs

Everything a normal invoice has (your details, the client's details, an invoice number, dates, payment terms; see what to include on an invoice), plus three things specific to hourly work:

1. The billing period. For example: "Work performed 1–31 October." This tells the client exactly which time you're billing for.
2. Your hourly rate. Stated clearly on the invoice, even if it's in the contract.
3. Hours broken down by task or category. Not every 15-minute block, but enough that the client can see where the time went.

How much detail is enough?

A good rule of thumb: enough that someone who wasn't in your head could understand what they're paying for.

Too little:

Development work — 42 h × $80 = $3,360

About right:

Homepage redesign — 18 h × $80 = $1,440 Checkout bug fixes — 9.5 h × $80 = $760 Client calls and revisions — 6 h × $80 = $480 Deployment and testing — 8.5 h × $80 = $680 Total: 42 h — $3,360

Four or five lines grouped by task is usually plenty. If a client wants day-by-day detail, attach a timesheet rather than putting fifty lines on the invoice.

A simple timesheet format

If you attach a timesheet, keep it plain:

Date	Task	Hours
Oct 2	Homepage layout	3.5
Oct 3	Homepage layout, client call	4
Oct 7	Checkout bug: payment form	2.5

Use the same task names as on the invoice so the totals match. A timesheet the client can check in a minute heads off most "what was this?" emails.

Rounding and minimum increments

Decide how you round time and say it once, in your contract or proposal. Common options are 15-minute or 6-minute (0.1 hour) increments. What matters is consistency: rounding every task up to the next hour without telling the client is the kind of thing that turns a good relationship sour.

Hourly with a cap or estimate

If you gave an estimate ("roughly 30–40 hours"), refer to it on the invoice when you're near or over it: "Estimate: 30–40 h. Actual: 42 h — additional time for extra revision round requested 14 Oct." Surprises are what cause disputes; explanations prevent them.

When to send hourly invoices

For ongoing work, invoice on a regular cycle (every two weeks or monthly) rather than waiting until the end of a long project. Smaller, regular invoices get approved faster and protect you if a project stalls. If the same client and rate repeat every month, see recurring invoices.

Payment terms

Put the due date in plain words on every invoice: "Due 14 November" is clearer than a code. If you use terms like Net 30, it's worth explaining what they mean (see invoice payment terms explained).

Make it quick to produce

If building hourly invoices takes you an evening each month, it's worth simplifying. In the free invoice generator you can enter hours as the quantity and your hourly rate as the price, set the due date, and download a clean PDF in a couple of minutes, no sign-up needed. A free NeatDue account also keeps your clients and invoice numbers organized, and the free plan covers a few clients and invoices a month.

The goal of an hourly invoice isn't to justify every minute. It's to make approving it the easiest thing on your client's list.