How to Invoice for Hours Worked (Hourly Invoice Guide)

Billing by the hour is straightforward: hours times rate. The hard part is that the client can't see the hours. A good hourly invoice gives them enough detail to trust the number without burying them in it.

Track time as you go

Reconstructing a month of hours from memory is how invoices end up both wrong and disputed. Use a timer app, a spreadsheet, or a notes file, and log:

• Date
• Start and end time (or duration)
• What you did, in one line
• Which client and project

Five seconds per entry, and you'll never argue about a timesheet again.

Decide your rules up front

Agree these with the client before you start, and note them on the invoice or in your contract:

• Rate: per hour, and whether different kinds of work have different rates
• Increments: most people bill in 15-minute or 6-minute (0.1 hour) blocks
• Rounding: up to the nearest increment, or to the nearest one
• Minimum charge: such as a 1-hour minimum for call-outs
• Travel time: billed, billed at a lower rate, or not billed
• Expenses: passed through at cost, or with a markup
• Caps: if the client needs a "not to exceed" limit, agree it before, not after

Three ways to present hours

Summary lines (most common)

Group by task or week. Clear and compact.

Description	Hours	Rate	Amount
Website maintenance: plugin updates, backups (week of 1 Sept)	3.5	$80.00	$280.00
New landing page build (8–12 Sept)	11.0	$80.00	$880.00
Client calls and email support	1.5	$80.00	$120.00
Total	16.0		$1,280.00

Daily entries

Better when the client wants to reconcile with their own records, or for staffing and contractor work.

Date	Description	Hours
2 Sept	Plugin updates, security scan	1.5
3 Sept	Backup restore test	2.0
8 Sept	Landing page wireframe	3.0
…	…	…

Put these in the item details, or attach a separate timesheet and keep the invoice to summary lines.

One line with an attached timesheet

"Development services, September 2026: 42.5 hours at $95 (timesheet attached)". Fine for established clients who trust your records.

Worked example

A bookkeeper billing a café for September:

• Rate: $55/hour, 15-minute increments
• Monthly bookkeeping: 6.25 hours
• Payroll for 8 staff: 2 hours
• Sales tax return: 1.5 hours

6.25 + 2 + 1.5 = 9.75 hours × $55 = $536.25

On the invoice, each of those becomes a line, with hours in the Qty column and $55 in the Rate column. In the generator, set the Qty column to "Hours" and the Price column changes to "Hourly rate" automatically.

Different rates on one invoice

If you charge more for some work (say, $120 for strategy and $75 for production), list them as separate lines. Don't average them; clients notice, and it hides the value of the expensive work.

Billing frequency

• Weekly or biweekly for high-hour contracts. Smaller invoices get approved faster and limit your exposure if the client stops paying.
• Monthly for ongoing, lower-volume work. Send on the same date each month.
• At the end only for short jobs.

Making hourly invoices easier to approve

• Describe outcomes as well as activity: "Fixed checkout error on mobile Safari (2.0 h)" beats "Debugging (2.0 h)".
• Flag anything unusual before invoicing: "The migration took 6 hours more than planned because of the old database; I'll include a note on the invoice."
• Keep consistent formatting month to month so the client learns to read it quickly.

If you're weighing whether to keep billing hourly, see hourly vs project pricing.