Fixed fees versus hourly billing: who carries the uncertainty

Aug 27
3 min read

Updated: 2 days ago

Introduction

Underneath every argument about billing models is a single question: if the work takes twice as long as expected, who pays for that?

Hourly billing puts it on the client. Fixed fees put it on the firm. Both are legitimate positions, and the right answer varies by matter type rather than being a policy for the whole practice.

1. Fixed fees versus hourly billing is about who carries uncertainty

Nothing else in the debate matters as much.

Where the scope is genuinely predictable, the firm can carry the risk cheaply and the client gets certainty. Where the scope depends on an opponent, a regulator or a discovery process, the firm cannot price it without either gambling or over-charging.

2. Fix the fee where you have done it fifty times

Repeatable work with a known shape.

Company formations, standard agreements, routine compliance, defined transactions, fixed-scope projects. You know the average time, the variance is small, and the client values knowing the number. This is where fixed fees are straightforwardly better for both sides.

3. Stay hourly where the scope is genuinely unknowable

Contentious matters, investigations, anything where the other side's behaviour determines the workload.

A fixed fee here is either a gamble you will sometimes lose badly, or a price high enough to cover the worst case, which over-charges every client whose matter proceeds normally. Neither serves anyone well.

4. Use staged fixed fees for long matters

The useful middle ground and the one most firms overlook.

Break a long matter into phases, each with a fixed price and a defined endpoint. The client gets predictability in manageable pieces, you re-price at each stage with better information, and nobody is committing to an unknowable total.

5. Scope in writing, whichever model you use

Fixed fees fail on scope, not on price.

Define what is included, what is excluded, how many revisions, what constitutes new work, and how variations are handled. The discipline hourly billing provided by default has to be created deliberately, and firms that skip this lose money consistently.

6. Give the client a cap if you stay hourly

Hourly billing's real problem is not the rate; it is the unbounded total.

An estimate with a cap, or a commitment to seek authorisation before exceeding a stated figure, removes almost all of the anxiety while keeping the model. Clients object to open-endedness far more than to hourly rates.

7. Do not let fixed fees discourage necessary work

The risk with fixed pricing is under-servicing.

If a matter is going badly and every additional hour reduces your margin, the incentive is to do less. Recognise that pressure and manage it, because a fixed fee that produces a worse outcome for the client destroys the relationship the pricing was supposed to improve.

8. Publish the fixed fees you can

Where you have a genuine fixed price, put it on the website.

Clients search for cost, find nothing, and contact the firm that published a figure. This is one of the more effective uses of fixed pricing and it is largely unrelated to the internal billing argument.

9. Measure effective hourly rate under both models

The comparison that settles the question empirically.

Track what you actually earned per hour on fixed-fee matters against your hourly rate on comparable work. Most firms discover that some fixed-price categories are considerably more profitable and others are consistently under-priced — which tells you exactly where to expand the model and where to pull back.

Conclusion

Decide by matter type rather than by firm policy, because the real question is who carries the risk of the work taking longer.

Fix fees on repeatable work you have done many times, stay hourly where the scope genuinely depends on other parties, use staged fixed fees for long matters, define scope in writing under either model, offer a cap or authorisation threshold if you remain hourly, guard against the under-servicing pressure fixed fees create, publish the fixed prices you have, and compare effective hourly rates across both models to see which categories work.