Tracking billable hours is only half the job. The other half — turning those hours into a correct invoice at the end of the month — is where agencies, consultants and IT service companies lose time and money: entries billed twice, hours forgotten, the wrong rate applied to the wrong person. Here is a practical workflow that keeps billable time and invoices in sync.
Step 1: Mark time as billable at the moment you track it
Decide when the work happens whether it’s billable. Internal meetings, sales calls and training usually aren’t; client work usually is. In Clocknico each time entry has a billable flag, and each project can be marked as billable, so entries on it are billable by default.
Step 2: Set the billing method per client
Not every client pays the same way. The three common models are:
- Hourly — the client pays for every billable hour at an agreed rate.
- Fixed price — an agreed amount for a project or a month, regardless of hours.
- Retainer — a monthly fee that includes a number of hours; extra hours are billed on top.
Clocknico’s Billing page lets you set the method per client, along with the client’s currency, payment terms and invoice details. That matters if you work with foreign companies: one client can be billed in EUR, another in USD or GBP.
Step 3: Decide which rate applies
The hourly rate can come from different places, and you should choose deliberately:
- Client rate — one rate for all work for that client (optionally overridden per project).
- Employee rate — senior people cost more than juniors, so the rate depends on who did the work.
Clocknico resolves the rate automatically for every entry — project, then client, then employee, or the other way round in employee mode — and uses the same logic in reports and invoices, so the numbers always match.
Step 4: Generate the invoice from tracked time
At the end of the period, pick the client and the date range and let the app build a draft invoice from the unbilled billable entries. You can group lines by project, by task, by employee or as a single line — whatever your client prefers to see. Re-billable project expenses (travel, licences, materials) can be added as invoice lines too, with an optional markup.
VAT is handled from your company settings: VAT rate, or a VAT-exempt note if you’re not registered. When you issue the invoice it gets a sequential number and a PDF you can send to the client.
Step 5: Never bill the same hour twice
This is the step spreadsheets get wrong. Once an entry is on an issued invoice, it should be locked to that invoice. In Clocknico, invoiced entries are linked to the invoice, so they won’t appear on the next one. If you cancel or delete a draft, the hours are released again.
Step 6: Check what’s still unbilled
The Billing page shows the unbilled amount per client. A quick look at the end of each month tells you who still needs an invoice — and which client is quietly accumulating hours you haven’t charged for.
Common mistakes to avoid
- Tracking time after the fact from memory. Use a timer; reconstructed weeks are always short.
- One global rate for everything. Different clients and different people deserve different rates.
- Mixing currencies in one total. Keep totals per currency instead of adding EUR to USD.
- Forgetting expenses. Log them on the project when they happen, with the receipt attached.
From hours to profit
Invoicing tells you what you charged. To know whether a client is actually worth it, compare that revenue with the cost of the hours spent — see our guide on how to calculate project profitability.
Billing and invoicing are included in every Clocknico plan, including the free plan for up to 5 users.