A Guide to Attorney Billing Increments for Law Firms

Lawyers don’t bill “hours.” They bill time entries converted into increments. The increment you choose is one of the few pricing levers that affects revenue without changing your hourly rate. It also affects perceived fairness, client disputes, write-downs, and compliance with outside counsel guidelines. A firm that bills in larger blocks can appear to “pad,” even when work is legitimate. A firm that bills in smaller blocks can undercapture time if lawyers delay entry or treat short work as “not worth recording.”

This guide explains Attorney Billing Increments from first principles, shows the math in a practical chart, and gives law firms an implementation checklist that improves realization and reduces billing friction.

What are Attorney Billing Increments?

Attorney Billing Increments are the units your timekeeping system uses to convert elapsed minutes into billable time. In most U.S. firms, the default increment is 0.1 hour—six minutes—because it maps cleanly to decimals and invoice math. Many firms also use 0.2 (12 minutes), 0.25 (15 minutes), or 0.5 (30 minutes) increments for specific clients, matters, or practice groups (Understanding Attorney Billing Increments, CosmoLex).

Two concepts matter operationally:

Increment size (e.g., 0.1 vs 0.25) determines how much rounding happens. Larger increments increase rounding. Rounding increases margin variability and client sensitivity.

The Minimum billable unit determines what happens to very short tasks. Some firms bill “a minimum of 0.1 for any substantive task.” Others allow “true to time,” still rounded to a tenth. Your policy must match client guidelines and your ethics obligations regarding fee reasonableness (Rule 1.5: Fees, American Bar Association).

Why 6-minute (0.1) billing became dominant

Six-minute billing did not win because it is perfect. It won because it is workable.

1. It creates a consistent decimal system for invoicing and accounting.
2. It reduces extreme rounding compared with 15-minute billing.
3. It is small enough to capture modern work patterns: emails, portal messages, quick client calls, and short document revisions.

For many clients, especially sophisticated corporate clients, the increment is less important than whether entries are compliant with guidelines (narratives, task codes, staffing, and prohibition on “block billing”). For individuals and small businesses, the increment can be the first thing they notice when an invoice shows 0.3 for a “quick call.”

The Attorney Billing Increments chart

This chart is the operational core for “billing in tenths.” It’s also a training tool for assistants, associates, and lateral hires.

Attorney Billing Increments chart (billing in tenths / 0.1 hour)

Alt text: Attorney Billing Increments chart converting minutes to tenths of an hour for legal billing (0.1 = 1–6 minutes, 0.2 = 7–12, etc.).

Minutes worked	Bill (hours)
1–6	0.1
7–12	0.2
13–18	0.3
19–24	0.4
25–30	0.5
31–36	0.6
37–42	0.7
43–48	0.8
49–54	0.9
55–60	1.0

This mapping appears in widely used “billing in tenths” reference charts used for appointed counsel and administrative billing systems (Chart for Billing in Tenths, Justice Administrative Commission).

Implementation tip: Put this chart inside your time entry screen as a hover tooltip or side panel. Do not make lawyers “do math” at the end of a long day.

0.1 vs 0.25 vs 0.2: how increment choice changes revenue, disputes, and realization

Increment choice is not a moral issue. It’s a tradeoff among revenue capture, client tolerance, and guideline compliance.

What larger increments do

When you bill in 0.25 (15-minute) increments, a 2-minute email becomes 0.25. A 9-minute call becomes 0.25. That rounding can trigger client anger, write-downs, and internal discomfort—especially in consumer-facing matters. It can also violate certain outside counsel guidelines that restrict minimums or require “actual time” (client-by-client).

Larger increments can make sense for:

• Flat-fee matters are internally tracked for profitability rather than invoiced by time.
• matters where the client expects block-based work, or
• institutional clients that expressly authorize 0.25 (rare in modern corporate billing, but it exists).

What 0.1 usually does better

Billing in 0.1 reduces the rounding jump and often reduces client disputes. A 2-minute task still rounds, but it rounds to 0.1 rather than 0.25. That difference shapes invoice optics.

Some practice-management sources argue that 6-minute increments can capture materially more revenue than 15-minute blocks because less time “falls through the cracks,” while still avoiding extreme rounding. One 2025 analysis aimed at midsize firms estimates 6-minute increments can capture about 15–20% more revenue than 15-minute blocks at the same hourly rates, primarily due to reduced underbilling and better time capture (Minimum Billable Increments: 0.1 vs 0.25, LeanLaw). Treat this as a directional estimate, not a universal rule, because matter mix and timekeeping discipline dominate results.

Why do some firms use 0.2 (12 minutes) or 0.1667 (10 minutes)

Some organizations use 10-minute (1/6 hour) increments to balance fewer entries with less rounding than 15 minutes. Others use 0.2 as an internal simplification. These choices are less standard, and they can complicate client-facing explanations. If you use them, document the policy, train staff, and make sure your billing platform handles them cleanly (Understanding Attorney Billing Increments, CosmoLex).

Ethics and compliance: what increment policies must not do

Increment policies do not exist in a vacuum. They sit inside professional responsibility rules, fee agreements, and client guidelines.

Reasonableness and transparency

Under ABA Model Rule 1.5, a lawyer may not charge an unreasonable fee or unreasonable expenses. The rule lists factors that include time and labor, novelty, customary fee, results, and other considerations (Rule 1.5: Fees, American Bar Association). Most jurisdictions adopt a version of this rule. A billing increment that systematically overstates time—especially when paired with vague narratives—creates risk in fee disputes and disciplinary complaints.

Minimum charges must be disclosed

If your engagement letter uses a minimum charge per event (e.g., “minimum 0.1 for any call/email”), you need to disclose it clearly and ensure it aligns with client expectations. Hidden minimums create reputational damage even when technically permissible.

Outside counsel guidelines can override firm defaults

For many corporate clients, your engagement letter is only half the story. The client’s outside counsel guidelines may require:

• specific increments (often 0.1),
• prohibition on billing for certain internal activities,
• requirements for task codes (often LEDES),
• narrative rules (no “review file,” no block billing),
• staffing limits (partner attendance restrictions).

Increment policy must be configurable at the client or matter level, not just firmwide.

The operational reality: increments don’t fix bad timekeeping

Firms lose more revenue to missed time and late entry than to choosing 0.1 vs 0.25.

Industry benchmarking content consistently shows lawyers spend only a fraction of the day on billable work, and firms need disciplined capture systems to avoid leakage. Even if the precise “average billable hours per day” varies across sources and firm segments, the operational conclusion holds: timekeeping friction is expensive.

A firm can adopt 0.1 increments and still underbill if lawyers:

• enter time days later (memory decay),
• don’t track short tasks,
• write vague narratives that trigger write-downs,
• block bill multiple tasks in one entry, or
• miscode tasks against client guidelines.

Choosing an increment policy that works for SMB firms

Most small-to-mid-size firms need a policy that balances profitability with client trust.

A practical default looks like this:

• 0.1 (6 minutes) firmwide default
• matter-level override when client guidelines specify something else
• No firmwide 0.25 unless your client base expects it
• minimum billing rules only where disclosed (and avoid “minimum 0.25” for consumer clients)

Then add a second layer: task-based minimums rather than blanket minimums. For example, “telephone call minimum 0.1” may be defensible if calls reliably involve context switching, conflict checks, and documentation. But “minimum 0.1 for reading any email” can look abusive in high-volume email matters unless the firm bundles communication into a flat-fee model.

Implementation: How to roll out Attorney Billing Increments without chaos

A policy is useless if your timekeepers fight it or ignore it.

Configure by client/matter, not by person

Attorneys move between matters with different guidelines. Your system should automatically apply:

• the correct increment,
• the correct task codes,
• narrative prompts,
• restrictions like “no internal conferencing” for certain clients.

Put the chart where time gets entered

Use the Attorney Billing Increments chart as an on-screen reference. It reduces conversion errors and shortens training time (Chart for Billing in Tenths, Justice Administrative Commission).

Prevent “block billing” by design

If your invoices regularly get cut, the cause is often narrative structure, not time. Many corporate reviewers reduce block-billed entries because they cannot audit reasonableness. Configure your system to encourage:

• one task per entry, or
• structured sub-entries within one timer session.

Audit for rounding inflation

Run a monthly audit:

• distribution of entries at 0.1, 0.2, 0.3, etc.
• time entry density per day
• percentage of time entered same day vs later
• top “write-down” narratives that triggered reductions

Use these audits to coach, not punish. If you punish, people stop recording time.

Revenue and client experience: how to talk about increments

Clients accept billing practices they understand.

For consumer clients, include a plain-language billing paragraph in the engagement letter:

• the increment used,
• how rounding works,
• What tasks may have minimums?
• How clients can request itemization.

For business clients, align with their guidelines and include a short billing addendum:

• increment,
• task codes,
• billing contacts,
• dispute process.

Billing disputes often become relationship disputes. Clear rules reduce both.

Frequently Asked Questions

Why do lawyers bill in 6-minute increments?
Six minutes equals 0.1 hour, which simplifies math and reduces extreme rounding compared with 15-minute billing. Many legal billing resources describe 0.1 as the most common standard for practical and transparency reasons.

Is billing in 15-minute increments allowed?
It can be, if the client agrees and it complies with applicable ethics rules and outside counsel guidelines. It often increases rounding and can increase client disputes in consumer matters. Many firms prefer 0.1 for that reason.

Do Attorney Billing Increments affect profitability?
Yes. They affect rounding and time capture behavior. Some practice-management analyses estimate that smaller increments can capture more revenue than larger blocks by reducing time leakage, though results vary by firm and matter mix (Minimum Billable Increments: 0.1 vs 0.25, LeanLaw).

Can a firm charge a minimum time per email or call?
A firm can set minimums if they are reasonable and clearly disclosed. ABA Model Rule 1.5 prohibits unreasonable fees and is the baseline ethical framework adopted in most jurisdictions (Rule 1.5: Fees, American Bar Association).

What is the best billing increment for small firms?
Most SMB firms do best with a default of 0.1, with matter-level overrides for client guidelines. The best policy is the one your team follows consistently, and your clients understand.

How do we reduce write-downs related to time entries?
Use clearer narratives, avoid block billing, match task codes to guidelines, and enter time the same day. Then, audit patterns and coach based on data.

Resources:

Rule 1.5: Fees (ABA Model Rules of Professional Conduct) — American Bar Association
https://www.americanbar.org/groups/professional_responsibility/publications/model_rules_of_professional_conduct/rule_1_5_fees/

Chart for Billing in Tenths (PDF) — Justice Administrative Commission
https://www.justiceadmin.org/court_app_counsel/ChartForBillingInTenths.pdf

A Guide to “Minimum Billable Increments”: Is Billing 0.1 (6 mins) or 0.25 (15 mins) Better? — LeanLaw
https://www.leanlaw.co/blog/a-guide-to-minimum-billable-increments-is-billing-0-1-6-mins-or-0-25-15-mins-better/

How to Calculate Billable Hours for Law Firms — LeanLaw
https://www.leanlaw.co/blog/how-to-calculate-billable-hours-law-firms/

A Guide to “Minimum Billable Increments”: Is Billing 0.1 (6 mins) or 0.25 (15 mins) Better? – LeanLaw
https://www.leanlaw.co/blog/a-guide-to-minimum-billable-increments-is-billing-0-1-6-mins-or-0-25-15-mins-better/

Billing Increment Chart: Converting Minutes to Decimal Hours – LeanLaw
https://www.leanlaw.co/blog/billing-increment-chart/

Billable Hours Chart for Attorneys – Virtual Staffing
https://www.virtualstaffing.com/blog/billable-hours-chart-attorneys

Why Do Lawyers Bill in 6-Minute Increments? – Bill4Time
https://www.bill4time.com/blog/why-do-lawyers-bill-in-6-minute-increments/