File Review in Law Firms: What the Rules Require, and the Numbers Nobody Publishes

Ask ten law firms what proportion of files they review and you will get ten answers, most of them invented. That is because no UK regulator or quality scheme publishes a sampling percentage. What the published sources do give you is a frequency floor, a corrective action deadline, a rule about how files must be selected, and a very uncomfortable evidence base about what is actually happening in practice.

This guide collects what is actually written down.

The only published numbers

There are three, and it is worth knowing that this is all there is:

• A frequency floor, from the Specialist Quality Mark guidance as collated by the Legal Aid Agency: it will not ordinarily be possible to justify file reviews less frequent than every three months.
• A corrective action deadline, from the Core Practice Management Standards: corrective action identified in a file review is completed within 28 days and verified.
• An annual obligation, from the same standards: conduct a review at least annually of the data generated by file reviews.

Everything else is risk-based and must be justified. Anyone quoting you a percentage is quoting a convention, not a rule.

What the Core Practice Management Standards require

The practice management standards used across the Law Society’s firm schemes contain the clearest statement of what a file review actually is. Requirement 5.10 requires a procedure for regular, independent file reviews of both the management of the file and the substantive legal content.

Three words in that do a lot of work. "Regular" sets the expectation of a cycle rather than an occasional exercise. "Independent" is the only place in any of these sources where independence is a mandatory qualifier. And "both the management of the file and the substantive legal content" rules out the common practice of reviewing only file housekeeping — dates, letters, costs information — while never checking whether the advice was right.

Requirement 5.10 also requires corrective action within 28 days, verified, and an annual review of the data the reviews generate. That last obligation is the one most firms fail: they conduct reviews diligently and never aggregate the findings to see what the pattern is.

Firms holding Lexcel should also note that file and case management is one of the three sections assessed at every annual maintenance visit, so this is not an area that gets a year off.

The Legal Aid Agency’s guidance is the most quotable source

The LAA’s supervisor requirements and guidance on effective supervision, in its version issued in July 2026, is the single most useful published document on file review method, because it collates the Specialist Quality Mark, Lexcel and SRA positions in one place. Its key statements:

• A supervisor must conduct file reviews for each caseworker they supervise.
• Reviews less frequent than every three months will not ordinarily be justifiable.
• The number of reviews must reflect the skills, knowledge and experience of the individual. No fixed number is given.
• The files reviewed should be representative, and must reflect the skills, knowledge and experience of the individual. Firms must define and explain their file selection criteria.
• The supervisor must record the outcome of file reviews together with details of any corrective action taken.
• Where work is high risk, a supervisor might need some awareness of every file. A trainee needs a higher proportion of their work checked.

It also states that there are no fixed supervisor-to-caseworker ratios — again, risk-based and justifiable rather than numerical. Firms holding the Specialist Quality Mark will recognise its requirements on supervision and training sitting behind this guidance.

Supervision is not file review

The SQM guidance makes a distinction most firms blur. It states that file review should be used as an internal quality-control mechanism, and then says plainly: supervision is not the same as file review.

It develops the point usefully. File review findings may form the basis of discussion at supervisory sessions but would never be the only source of development information. Supervision intensity should fall as competence is demonstrated — for instance through limited adverse file review findings. And findings should inform how future cases are allocated.

So the three things are distinct and each needs its own evidence: supervision is the ongoing relationship, file review is a quality-control sample, and competence assessment draws on both.

The SRA’s position: no fixed rate, but one hard rule on sampling

The SRA’s effective supervision guidance, first published in November 2022 and last updated in June 2026, is explicit that there is no single model of supervision and no fixed frequency. It is risk-based throughout.

It does, however, contain one rule that firms routinely breach without noticing. Where work is high risk or complex, the supervisor might need some awareness of every file. For lower-risk work it might be reasonable to see only a small sample — and then the critical qualification: they should make sure the sample includes work that the supervisee does not ask them to look at.

A review process built entirely on files the fee earner submits is not a sample. It is a curated selection, and it fails the guidance.

The guidance also sets out what checks should cover: substantive legal accuracy and client needs, adherence to firm sign-off policies, ethical and regulatory issues, and file management. On records, it expects supervision to be evidenced — by emails, file notes and time records — without requiring every informal discussion to be written up. Firms must be able to show the arrangements they chose, why, and how they assure effectiveness.

The guidance does not mandate review outside the supervisory line, but it names as good practice peer review by senior staff for novel or complex issues, a designated quality control reviewer for high-risk engagements, and proportionate audit and quality assurance measures. It also cites enforcement examples: a firm fined after a conveyancing partner carried out no meaningful checks, and another after a part-time supervisor did not review casework. In a further example, sampling only a small proportion of high-risk work was found not to be effective, as was a solicitor with their own caseload seeing paralegals’ work only every few months.

The underlying duties sit in the Codes: competence and supervision at paragraphs 3.2, 3.3, 3.5 and 3.6 of the Code of Conduct for Solicitors, and at paragraphs 4.2, 4.3 and 4.4 of the Code of Conduct for Firms, with the compliance officer duties covered in our guide to COLP and COFA responsibilities.

What the SRA found when it looked at real files

The SRA’s thematic review of probate and estate administration, published in December 2024, is the best published evidence base on whether file review actually happens. Reviewing two matters at each firm, opened since February 2022, it found:

• Of 30 files handled by fee earners, only nine showed evidence of supervision.
• Of 20 files handled by heads of department or sole practitioners, only one recorded supervision, peer review or oversight.
• Twelve of 25 heads of department or sole practitioners received no supervision, oversight or peer review at all.

The self-review gap at the top of firms is the headline finding, and it is the strongest published argument against relying on self-review by senior fee earners. The review’s own checklist tells firms to have an effective system for supervising client matters, which may include oversight or peer review of the work of heads of department and other senior staff.

It also published an example of good practice worth copying: at one firm, each fee earner has three files reviewed by a supervisor every month, partners’ files are reviewed by other partners, review forms are kept on the files, and corrective actions are completed within 28 days. That is the only concrete review rate in any of these sources, and it is one firm’s practice rather than a standard.

On learning and development, the same review found that of 30 records examined, 28 recorded activity but only eight evaluated effectiveness — which is the continuing competence gap in one statistic.

Designing a defensible file review system

Pulling the sources together, a system that could survive an assessment or an SRA review has seven features:

• Written selection criteria that explain how files are chosen and why that is representative.
• A proportion of files selected by the reviewer, not submitted by the fee earner.
• Review of substantive legal content as well as file management.
• Frequency tied to each individual’s experience, with higher rates for trainees and high-risk work, and not less often than quarterly where a quality standard applies.
• Independence where it matters most — including peer review of heads of department and sole practitioners.
• Recorded outcomes and corrective actions, completed within 28 days and verified.
• An annual aggregate review of what the file reviews collectively show, feeding the training plan.

That last point is where file review connects to competence. The SRA’s continuing competence approach asks solicitors to reflect, identify learning needs, address them, record activity and evaluate effectiveness. File review data is the most reliable source of the first two, and most firms never use it that way.

Frequently asked questions

What percentage of files should we review?

No published source gives a percentage. The obligations are that selection is justified and representative, that frequency reflects the individual, and — where a quality standard applies — that reviews are not less frequent than quarterly.

Must file reviews be independent?

The Core Practice Management Standards require regular, independent file reviews. The SRA guidance does not mandate independence but requires samples to include work the supervisee did not choose, and treats absent peer review of senior staff as a weakness.

How quickly must corrective action be completed?

Within 28 days, and verified, under the Core Practice Management Standards.

Does supervision count as file review?

No. The SQM guidance states that supervision is not the same as file review, and that review findings would never be the only source of development information.

What records are needed?

Recorded review outcomes and corrective actions. The SRA expects supervision to be evidenced through emails, file notes and time records, and firms to be able to explain the arrangements chosen and how effectiveness is assured.

Who reviews the partners’ files?

On the SRA’s own findings, in most firms nobody does — and it treats that as the central weakness. The good-practice example it published has partners’ files reviewed by other partners.

Turning review findings into training

The gap the SRA keeps finding is not that firms do not train. It is that they do not evaluate whether training worked, and do not connect what file reviews reveal to what people are taught next. Learnsignal builds CPD and compliance training for firms with completion and evaluation records designed for that loop — including the AML training and ethics, conflicts and client care material that file reviews most often flag. To see the catalogue, explore our CPD courses or see pricing for teams.