Getting paid

How to Bill Hourly: Timesheets, Rounding & Invoices

Hourly billing done right: setting your rate, tracking time, rounding rules, what to show on an hourly invoice, caps and estimates, and avoiding disputes.

4 min read

Hourly billing is the simplest pricing model to explain — you pay for the time I spend — and one of the easiest to get wrong in practice. Untracked time, inconsistent rounding and vague invoice lines lead to underbilling on your side and suspicion on the client’s. This guide covers how to set it up properly, from rate to timesheet to invoice.

When hourly billing makes sense

Works well for Less suited to
Open-ended or evolving work (support, consulting, maintenance) Well-defined deliverables (a logo, a website with fixed scope)
Work where the client controls the volume (edits, meetings) Work where you’re much faster than average — you’re penalised for efficiency
Early relationships before scope is understood Clients with fixed budgets who need certainty
Regulated professions with hourly norms (legal, accounting) Highly creative or value-based work

Many freelancers mix models: hourly for discovery or support, fixed price for defined projects, and retainers for ongoing work.

Step 1: Set an hourly rate that actually covers your costs

Your rate has to pay for non-billable time (admin, sales, learning), expenses, taxes, holidays and sick days — not just the hours on the timesheet. A simple formula:

Hourly rate = (target annual income + annual business costs) ÷ billable hours per year

Most independents bill far fewer than 2,000 hours a year; somewhere between 1,000 and 1,400 billable hours is a realistic planning range for many, once admin and time off are accounted for. Our hourly rate calculator does the maths, and pricing your freelance services covers how to position the number.

Step 2: Agree the rules before you start

Put these in your contract or quote:

  • Rate (and any different rates for different work — e.g. meetings vs. development, rush or weekend work)
  • Billing increment — e.g. 15 minutes, or 6 minutes (0.1 hour) as many law firms use
  • Minimum charge — e.g. one hour for any call-out or ad-hoc request
  • What’s billable — meetings? travel time? email? research?
  • Estimate or cap — e.g. “estimated 30–40 hours; we’ll ask for approval before exceeding 40”
  • Invoicing frequency — weekly, every two weeks or monthly
  • Expenses — whether they’re recharged and with what evidence

Step 3: Track time as you go

Reconstructing hours at the end of the month is how freelancers lose income. Track in real time, with enough detail to describe the work later:

Date Start–end Hours Task Project
3 Nov 09:10–11:40 2.50 Checkout bug investigation & fix Shop v2
3 Nov 14:00–14:45 0.75 Call with Sam re: payment provider Shop v2
5 Nov 10:00–13:15 3.25 Payment provider integration Shop v2

A spreadsheet works fine; a timer app helps if you switch tasks often. Note what you did, not just how long — that’s what turns into invoice descriptions.

Step 4: Round consistently

Pick one rounding rule, state it, and apply it everywhere:

Increment 22 minutes becomes Notes
6 min (0.1 h) 0.4 h (24 min) Common in legal and accounting
15 min (0.25 h) 0.5 h (30 min) Common for freelancers and consultants
30 min 0.5 h Coarse; better as a minimum charge than a general rule

Round each entry or the daily total, but be consistent. Rounding every 3-minute email up to 15 minutes will be noticed and resented; round the day’s total, or log small items together.

Step 5: Write a clear hourly invoice

An hourly invoice should let the client check your work without asking:

Description Hours Rate Amount
Shop v2 — checkout bug investigation and fix (3 Nov) 2.50 $95 $237.50
Shop v2 — payment provider integration (5–7 Nov) 9.25 $95 $878.75
Shop v2 — meetings and calls (3, 6 Nov) 1.50 $95 $142.50
Total 13.25 $1,258.75

Good practice:

  • Group by task or week, with date ranges, instead of one line per day.
  • Show total hours so the client can compare against any cap.
  • Attach or offer the timesheet for the period.
  • Separate expenses from time.
  • State the period covered (“Services 1–15 November 2026”).

The invoice generator accepts decimal quantities, so 13.25 hours × $95 calculates exactly.

Caps, estimates and “not to exceed”

Clients worry hourly work is open-ended. Reassure them with structure:

  • Estimate ranges — “30–40 hours” — with a promise to flag early if you’ll exceed it.
  • Caps — “not to exceed 40 hours without written approval”.
  • Budget burn reports — a one-line weekly update: “18 of 40 hours used.”

If you hit a cap, stop and ask before continuing. Unapproved overruns are the most common cause of invoice disputes.

Billing frequency

Bill hourly work at least monthly; weekly or fortnightly for new clients or large volumes. Shorter cycles mean smaller invoices (easier to approve), earlier warning if the client won’t pay, and less time to forget what was done.

Common mistakes

  • Forgetting to track small tasks. Ten untracked 10-minute calls a week is roughly seven hours a month.
  • Vague descriptions like “Development — 40 hours”.
  • Changing the rounding rule between invoices.
  • Billing for learning the client should not pay for (e.g. learning a tool you claimed to know). Be fair; trust is worth more than the hours.
  • Never revisiting your rate. Review it at least once a year.

When to move away from hourly

If you consistently finish faster than clients expect, or clients ask for a fixed number, convert your hourly estimate into a fixed project price — with clear scope and revision limits — or a monthly retainer. You’ll be rewarded for efficiency instead of penalised.

Rules on billing practices can apply in regulated professions and in consumer contracts. This guide is general information, not legal advice.