Most boards need both. Internal reviews, run by the company secretary in the years between, cost officer time rather than fees and build continuity. An externally facilitated review, expected at least every three years for FTSE 350 companies under the UK Corporate Governance Code, brings independence and the licence to question the chair directly.
Chairs and company secretaries face the internal vs external board effectiveness review question every year, not once. This piece is for the person scoping this year's round: a FTSE 350 company secretary counting three-year intervals, a charity chair with a governance review falling due, or a trust secretary preparing for a well-led assessment. If you have already settled the question and want the process itself, our guide to running the annual board performance review covers the full cycle.
What the board needs to decide
Five questions settle the approach before the chair signs anything off.
- Is this a mandated year? For a FTSE 350 company, Provision 21 of the UK Corporate Governance Code 2024 expects an externally facilitated board performance review at least every three years. Charities and NHS provider trusts work to their own intervals (see the sector table below).
- Is there a question only an outsider can ask? An unresolved concern about the chair's own effectiveness, a strained chair and chief executive relationship, or a pattern of debate that no one raises in the room. If one of these is live, the mandated year is not the only reason to go external.
- Who collects and sees the raw responses? Internal reviews concentrate that role in the company secretary or the chair. Where directors are being asked about those same people, the design has to answer for it.
- What does the budget buy? External facilitation is priced against board size, the number of interviews and the depth of reporting. If the fee only stretches to a light-touch questionnaire, an internal round with real one-to-one conversations may produce more.
- Does the preferred reviewer have any other connection to the company? Provision 21 requires the external reviewer to be identified in the annual report, with a statement of any other connection it has with the company or individual directors. Establish that before appointment, not at drafting.
Internal vs external board effectiveness reviews: the three options compared
The choice is usually presented as a binary. In practice, most well-run boards operate a third option: an alternating cycle where internal and external rounds are planned together rather than decided one year at a time.
| Dimension | Internal review | Externally facilitated review | Alternating cycle |
|---|---|---|---|
| Who runs it | The company secretary or governance team, commissioned by the chair | An independent facilitator appointed by the chair | Both, in a rhythm fixed in advance |
| Direct cost | Officer time rather than fees | A fee scoped to board size, interview count and reporting depth | External fees in one year out of three |
| Candour on the chair | Constrained: the chair usually sits in the reporting line | Independent: no working relationship to protect | Independent in the external year, tracked internally between |
| Benchmarking | Against the board's own history only | Against other boards the facilitator has reviewed | Both, where the internal instrument reuses the external questions |
| Continuity between rounds | Strong: the same people hold the institutional memory | Depends on whether the same facilitator returns | Strong, provided the action plan carries across years |
| Annual report disclosure | Describe how the review was conducted (Provision 23) | Name the reviewer and state any other connection (Provision 21), alongside Provision 23 | Both, depending on the year |
| Suits | The years between external rounds, and boards with stable, recently tested composition | A mandated year, a new chair, or an unresolved question about boardroom dynamics | Any board that expects to be reviewed externally more than once |
How does the alternating internal and external review cycle work?
In a typical FTSE 350 three-year cycle, the board runs an internal review in years one and two and commissions an externally facilitated review in year three, then repeats. The Code sets a maximum interval, not a minimum: nothing prevents a board from going external more often when a specific question warrants it.
Planning the cycle rather than the year is what stops the internal rounds being filler. Year one picks up the external facilitator's action plan and tests whether the agreed changes stuck. Year two takes a narrower cut, often a single committee or a specific theme such as the quality of board papers. Year three hands the facilitator a board that already knows what it committed to, which is a far more productive starting point than an open-ended questionnaire.
This framing is not unique to the UK. Euronext Corporate Solutions describes the same external, internal and hybrid pattern as general international practice (checked 3 August 2026). Treat that as corroboration of a common approach rather than a rule: the interval that binds a UK board is the one in its own code, and for FTSE 350 companies that is the Code's three-year external expectation, which applies to financial years beginning on or after 1 January 2025.
What can an external facilitator do that an internal review cannot?
Three things: question the chair's own effectiveness without a career or working relationship at stake, offer comparison with other boards the facilitator has reviewed, and collect director views as someone with no ongoing relationship to protect. Directors tend to speak more freely to a person they will not see at next month's meeting.
That is a structural point, not a criticism of the company secretary running the internal round. A company secretary who reports to the chair cannot credibly be the sole channel for candid feedback about the chair, however well they handle it, and directors calibrate what they say accordingly.
What an internal review does better is memory and follow-through. The company secretary knows which action from two years ago quietly lapsed, which director has raised the same concern three rounds running, and which improvement was real rather than reported. An external facilitator arriving cold has to reconstruct that, and usually cannot in the time available. If you are weighing up who to appoint for the external year, our guide to choosing a board evaluation provider in the UK sets out what to ask.
How often does each sector expect an external review?
FTSE 350 companies: at least every three years under Provision 21 of the UK Corporate Governance Code. Larger charities: an external expert involved in the governance review every three years under the Charity Governance Code. NHS provider trusts: an external board effectiveness review every three to five years.
| Sector | External involvement expected | Where it comes from |
|---|---|---|
| FTSE 350 listed companies | At least every three years, commissioned by the chair, with the reviewer named in the annual report | UK Corporate Governance Code 2024, Provision 21 |
| Larger charities | An external expert involved in the governance review every three years | Charity Governance Code, as set out in NCVO's guidance on carrying out a governance review |
| NHS provider trusts | An external board effectiveness review every three to five years, aligned to the well-led framework | NHS England, well-led framework |
| Smaller and unlisted organisations | No formal interval | No applicable code provision |
Two clarifications on that table. An FCA-regulated firm that also sits in the FTSE 350 falls under Provision 21 like any other listed company: financial services regulation does not create a separate review clock, and the same three-year external expectation applies. And for a smaller charity's trustee board, or an unlisted company of any size, nothing forces an external round at all. That is precisely where boards drift, because an internal-only process tends to reproduce the board's existing view of itself. Periodic external challenge, even every four or five years, is the guard against it.
If you want the conceptual grounding behind what these reviews actually measure, our overview of board effectiveness frameworks sets out how the main models divide the territory.
Common mistakes when choosing between internal and external
Treating the external review as a compliance purchase. A facilitator engaged once, in the year the interval expires, with no connection to the internal rounds either side, produces a report that lands and disperses. Provision 22 expects the chair to act on the results, and Provision 23 expects the annual report to describe how the review was conducted and what followed. Both are much easier to write when the external year sits inside a cycle.
Appointing a reviewer with an undisclosed connection. A firm that also sells the company executive search, audit or consultancy services is harder to disclose cleanly under Provision 21, and the disclosure is the point at which the awkwardness becomes public. The Chartered Governance Institute's Code of Practice for board reviewers is a reasonable benchmark to hold a prospective facilitator against, and asking how they meet it is fair due diligence.
Letting the subject collect the evidence. In an internal round, the chair should not be the person gathering and interpreting feedback on the chair, and a committee chair should not be the sole channel for views on their own committee. Route those specific questions through the senior independent director or an independent third party, even in an internal year.
Skipping external review because no rule requires it. For most charities, unlisted companies and smaller organisations, this is a choice rather than an obligation, which is exactly why it gets deferred. The cost of never testing the board's self-perception against an outside view is rarely visible until something goes wrong.
Running the same instrument every year regardless. Repeating an identical questionnaire produces comparable data and diminishing engagement. Keep a stable core of rating questions for trend tracking, then change the open questions and the focus area each round.
Choosing this year's review type
The practical answer for most boards is a planned three-year rhythm: two internal rounds that carry the action plan forward, one externally facilitated round that tests what the board cannot see about itself, and a single evidence base that both draw on. Decide the rhythm once, in the boardroom, and the annual question becomes an operational one rather than a debate.
If this is your external year, BoardServe's board effectiveness reviews cover the board, its committees, the chair and individual directors in one cycle, with the findings, action plan and follow-through held in one place so the internal years have something to build on.