What Is Timesheet Locking (and Why Billing Teams Need It)

If anyone on your team can edit a time entry after the invoice has gone out, your records and your invoices will eventually disagree — and that gap is where client disputes and lost trust live. Timesheet locking is the boring feature that quietly prevents all of it.

Here’s exactly what it is, why bill-by-hour teams need it, and how to use it well.

What timesheet locking actually is

Timesheet locking lets an administrator set a cutoff date, after which all time entries before that date become read-only. Nobody — not even the person who logged the time — can edit or delete a locked entry without an admin unlocking the period first. It turns your time log from an editable draft into a permanent record for closed periods.

Think of it like closing the books in accounting: once a period is closed, the numbers are final. You can still work in the current period, but the past is fixed.

Why it matters for billing teams

• Invoice integrity. The hours you invoiced are the hours in the system — permanently. No silent edits after the fact.
• An audit trail. For accounting firms and professional services, a defensible, unchangeable record of billable time is often a requirement, not a nice-to-have. See how we treat this in NovaClock security.
• Fewer disputes. When a client questions an invoice, you can show a record that provably hasn’t changed since you billed it.
• Payroll accuracy. If time drives pay, locking stops retroactive changes from quietly altering what someone is owed.

How locking works in practice

A typical locking workflow looks like this:

1. Team logs time normally throughout the period.
2. The period closes — say, the end of the month or your billing cutoff.
3. An admin sets the lock date. Every entry on or before it becomes read-only.
4. You invoice from a set of numbers that can no longer move.
5. If a genuine correction is needed, an admin unlocks, the change is made, and the period is re-locked — deliberately, and by someone with the authority to do it.

The key is that editing closed time becomes a deliberate, permissioned action rather than something anyone can do by accident.

When should you lock?

Lock as soon as a billing period is finalized and invoiced — not before (you still need to make legitimate edits while the period is open), and not weeks later (the longer you wait, the more likely something drifts). For most teams that means locking the prior month within a few days of sending invoices.

Common mistakes

• Never locking at all — relying on trust and hoping nobody edits history. It works until the one time it doesn’t.
• Locking too early, before corrections are in, so you’re constantly unlocking.
• Treating locking as a paid add-on you’ll “get to later.” Many trackers gate it behind higher tiers; if billing integrity matters, it should be part of your baseline, not an upgrade. It’s included on every NovaClock plan.

Frequently asked questions