MDU, MPS, MDDUS: what actually differs for locum GPs

CNSGP covers NHS clinical negligence for GPs from April 2019. Discretionary indemnity from the Medical Defence Union (MDU), Medical Protection Society (MPS), or Medical and Dental Defence Union of Scotland (MDDUS) covers everything else. For a locum GP, everything else is a lot: private work, GMC proceedings, coroner's inquests, inquiries, good-Samaritan acts, complaints, and press representation. The choice between the three is about service and fit more than about headline fees.

Cost

For a locum GP working typical sessions with no private practice, all three organisations publish fees in a similar range. For 2026, expect roughly £400–£900 per year, with significant variation by:

• Session count per week
• Whether you do any private GP work alongside NHS
• Whether you do any aesthetic work (generally excluded or surcharged)
• Years qualified (newly qualified GPs pay less)

MDDUS is often slightly cheaper for Scotland-based GPs. MDU and MPS are broadly comparable for England and Wales.

What discretion actually means

None of these bodies guarantee cover. They have discretion to refuse a claim if, for example, you did not act in good faith. In practice, refusals for genuine locum work are very rare, but "discretionary" is not the same as an insurance contract, which is why the FCA regulates some defence products as insurance but not all.

MDU offers insurance-backed products for some risks alongside discretionary cover. MPS and MDDUS are discretionary across their offering. The distinction matters for:

• Certainty: an insurance contract has enforceable terms
• Cover persistence: discretion can be withdrawn
• Historical claims: what happens if you cancel or switch

Ask specifically which of your risks are insurance-backed and which are discretionary when you renew.

Service quality

This is where GPs vary most in their loyalty.

Responsiveness. How quickly do they get back on an out-of-hours query? Try asking each one a trivial question before joining; the response time and tone tell you plenty.

Named case handlers. When a complaint lands, do you get a named barrister or a case-handling pool? Named handlers build familiarity with your case; pools lose time at every handover.

GMC experience. Most locum GPs never face a GMC case. When one happens, it is weeks of your life. Ask directly: how many GMC cases do you handle annually; who represents me; how many go to tribunal.

CPD and education. All three offer member CPD. Content varies. Some GPs move between them every few years partly for the education.

Quirks worth knowing

• Run-off cover after you retire or leave practice: terms vary. Discretionary organisations commit to cover historical work but with discretion; retirement-specific products differ.
• International work: cover for overseas sessions varies significantly. MDU has historically been more flexible for UK GPs doing short-term overseas work.
• Aesthetic and cosmetic work: all three scrutinise this carefully. Surcharges or exclusions common. Get the confirmation in writing before you start the service.
• Telemedicine: all three cover UK-to-UK consultations. Consultations to patients outside the UK are a separate conversation.

CNSGP, what it does and does not cover

CNSGP (Clinical Negligence Scheme for General Practice, run by NHS Resolution) covers NHS clinical negligence for GPs and their practice team from 1 April 2019. It is automatic, you do not apply, and free.

What it does not cover:

• Private work, including aesthetic, insurance-medical, and occupational-health
• GMC investigations and referrals
• Complaints handling
• Coroner's inquests
• Disciplinary or employment issues
• Good-Samaritan acts off duty

So CNSGP is necessary but not sufficient. You still need discretionary indemnity for everything else.

Choosing

Most locum GPs make the decision on recommendation from colleagues plus one of these:

1. A bad experience with one organisation's response time
2. A specific private-practice risk that one organisation handles better
3. Fee difference of more than £150 for identical cover

The free-trial approach is worth it: try one for a year, move if dissatisfied. Switching is not complicated as long as you notify both organisations of overlap and confirm continuity of cover.

What not to do

• Do not cancel existing cover before the new one confirms. Even a day's gap in run-off cover can matter if a historical claim surfaces.
• Do not assume employer indemnity extends to locum work. It rarely does.
• Do not let a quote become "confirmed cover" in your head. You have cover when you have a membership number and a certificate, not before.

Sessional stores your indemnity certificate alongside your other professional documents and sends a reminder 30 days before expiry. See our documents guide.