Block billing is the practice of combining multiple legal tasks into a single time entry instead of recording each task separately.
“Review documents, draft memo, call with client, analyze issues — 8.4 hours.”
The total time may be reasonable, but the entry makes it impossible to see how much time was spent on reviewing, drafting, calls, or analysis.
For in-house legal teams, that lack of detail makes invoices harder to review, budgets harder to explain, and spend data less useful.
Block billing is not necessarily an attempt to overcharge. It often reflects habit or time-entry convenience. The problem is that it prevents the client from evaluating individual tasks.
This guide explains how to recognize block billing, why it matters, and how to address it consistently without creating unnecessary friction with outside counsel.
What is block billing?
In legal billing, block billing occurs when a timekeeper records two or more tasks under one combined amount of time. A task-based entry records each activity and its time separately.
Instead of recording work like this:
Review draft agreement — 1.2 hours
Revise indemnification clause — 0.6 hours
Call with business team — 0.5 hours
You might see something like this instead:
Review agreement, revise provisions, call with business team — 2.3 hours
The total time may be perfectly reasonable. But once tasks are combined like this, it becomes difficult to evaluate:
which tasks took the most time
whether work was staffed appropriately
whether the time spent was reasonable
how similar work compares across matters or firms
For teams trying to bring structure and predictability to legal spend, that lack of visibility matters.
Why block billing is a problem for legal departments
1. You lose visibility into where time actually goes
When tasks are bundled together, you can’t easily see whether time was spent on research, drafting, internal discussions, or administrative work.
That makes it difficult to answer simple questions like:
Why did this motion cost twice as much as the last one?
Are we overpaying for research?
Are partners doing work that associates could handle?
Without that visibility, budgeting and forecasting become much harder.
2. It makes invoice review much more difficult
Block billing forces reviewers to evaluate time entries without enough context.
For example:
Draft discovery requests, revise responses, review documents — 6.5 hours
Was most of the time spent drafting? Reviewing documents? Researching the law?
There’s no way to know.
This is why many organizations include “no block billing” language in their billing guidelines.
3. It weakens spend analysis
Many legal teams now want to answer questions like:
How much do we typically spend on contract review?
What does an average employment matter cost?
Which firms are most efficient on similar work?
Block billing makes those insights much harder to generate because tasks aren’t clearly separated.
In other words, block billing doesn’t just affect invoice review, it affects the quality of your legal spend data.
Why law firms use block billing
It’s worth recognizing that block billing usually isn’t an attempt to hide work.
More often it happens because:
time entry systems make separate entries cumbersome
lawyers reconstruct time at the end of the day
firms assume clients don’t need detailed breakdowns
lawyers were simply trained to record time this way
The good news is that most firms adapt quickly when expectations are clear.
How to address block billing without creating friction
The goal isn’t perfect invoices. The goal is reasonable transparency.
Here are a few approaches that tend to work well.
1. Set expectations in your billing guidelines
Start by defining the rule in your outside counsel billing guidelines. The policy should explain whether tasks must be itemized, when clarification is required, and how noncompliant entries will be handled.
For example:
Time entries should describe a single task. Multiple tasks should be recorded separately. Entries combining multiple tasks may be reduced.
Most firms are already familiar with language like this.
Apply the rule consistently across firms and matters. If it exists but is never enforced, it will quickly be ignored.
2. Focus on larger entries first
You don’t need to challenge every small time entry.
Instead, focus on entries that involve:
several hours of work
strategically important tasks
high-value matters
Even modest improvements in large entries dramatically improve invoice visibility.
3. Ask for clarification before requesting adjustments
Often the easiest approach is simply asking for more detail.
For example:
“Could you provide a bit more detail on the tasks included in this entry so we can better understand how the time was allocated?”
Many firms will respond quickly without any pushback.
4. Follow a documented escalation rule
When clarification does not resolve the issue, follow the response defined in your billing guidelines or engagement terms.
requesting revised, itemized time entries before approval
holding or adjusting noncompliant charges when the engagement terms allow it
The goal is not to impose an arbitrary penalty. It is to use a predictable process that firms understand before invoices are submitted.
Block billing example: combined vs. task-based entries
Imagine two invoices for similar work.
Invoice A (block billed)
Review agreement, revise provisions, conference with team, research issue — 5.6 hours
At a glance, it’s impossible to tell:
which task consumed the most time
whether research dominated the work
whether senior lawyers handled routine tasks
Invoice B (tasks separated)
Review agreement — 1.5 hours
Revise indemnification clause — 1.0 hour
Research regulatory issue — 2.2 hours
Internal conference — 0.9 hours
Immediately, the picture becomes clearer:
research consumed the largest portion of time
internal conferencing took nearly an hour
future budgets can be estimated more accurately
Across dozens or hundreds of invoices, this kind of clarity makes a significant difference.
The bigger goal: better data, not just cleaner invoices
It’s tempting to think of block billing as just an invoice formatting issue.
But the real impact is on data quality.
When time entries are clear and consistent, legal teams can:
understand how work is actually being performed
compare firms and staffing approaches
budget matters more accurately
identify opportunities to reduce cost
Improving billing clarity tends to pay dividends far beyond a single invoice review.
A simple block billing policy to start with
If your organization hasn’t addressed block billing yet, a simple starting point is:
Add a short block-billing clause to your billing guidelines
Ask for clarification when large entries appear
Track patterns across firms over time
Most firms adapt quickly once expectations are clear.
And over time, those small improvements make invoice review faster, budgets more accurate, and legal spend easier to manage.
Frequently asked questions about block billing
What does block billing mean in legal invoices?
Block billing means combining multiple tasks under one time entry and one total amount of time. Because the tasks are not itemized, the reviewer cannot determine how much time each activity required.
What is an example of block billing?
An entry such as “review documents, revise brief, call client — 6.2 hours” is block billed because several distinct tasks share one time total. A task-based invoice would record each activity and its time separately.
Why do legal departments restrict block billing?
Legal departments restrict block billing because it makes reasonableness, staffing, guideline compliance, budgeting, and matter-level comparisons harder to evaluate.
How should an invoice reviewer respond to block billing?
Start by checking the billing guidelines and engagement terms. For a material entry, request an itemized explanation before applying the department’s documented escalation or adjustment process.
Turn clearer billing into better spend data
Clear time entries make invoice review faster and create more useful data for budgeting, staffing analysis, and outside counsel conversations. Poppy helps legal teams review line items consistently and identify billing patterns across firms and matters.
Download the outside counsel billing guidelines template, use the legal invoice review checklist, or explore Poppy’s invoice review workflow.