The SRA’s £2 million minimum was a sensible floor in 2000; for a modern firm doing residential conveyancing volume or any commercial work of substance, it stops being meaningful exposure protection at about the first serious claim.
The SRA Minimum Terms and Conditions of Professional Indemnity Insurance (MTC) set the floor on solicitors’ PI: £2 million any one claim for unincorporated practices, £3 million for incorporated practices. Most firms of any scale buy top-up layers above this, often building a tower of £5 million, £10 million, £25 million or higher depending on work type and client expectations. Top-up cover is a separate market with its own dynamics, its own wordings, and — critically — its own relationship to the MTC. The primary policy must be MTC-compliant. The top-up layer is not. This guide explains when top-up is genuinely needed, how the market structures it, the wording differences that matter, and how to think about lender panel requirements and single-large-matter exposure. The framework is set by the SRA Indemnity Insurance Rules; the statutory anchor is the Solicitors Act 1974.
Top-up cover sits above the firm’s primary MTC policy and responds once the primary limit has been exhausted. The trigger is straightforward: when the primary insurer has paid out its £2 million (or £3 million) limit on a covered claim, the top-up layer engages from that point upwards.
In practice, the buying conversation comes up in four scenarios.
Residential conveyancing volume. Conveyancing fee income alone often justifies a top-up layer. A firm doing 300+ residential transactions a year is exposed to clustered claims — title defects on a new-build site, identity fraud rings, lender panel claims arising from systemic process issues — that can aggregate under MTC clause 2.5 into a single claim well above the primary limit. The exposure is not the single property value; it is the aggregated value of every transaction sharing the alleged systemic failing.
Commercial property and corporate. Single-large-matter exposure is the second driver. A solicitor acting on a £40 million commercial property purchase, an M&A transaction, or a high-value financing has potential exposure well in excess of the £2 million primary in respect of a single matter — a missed encumbrance, a defective warranty, an unenforceable security.
Lender panel requirements. Major residential lenders publish panel conditions that often require minimum PI cover above the SRA floor. The CML / UK Finance Lenders’ Handbook has historically been the touchstone, with individual lenders sometimes setting their own higher minimums for higher-value transactions or specific panels. A firm losing panel status because its PI tower is too low can lose a large slice of its fee income overnight.
Client expectation. Commercial clients of any size now routinely ask for evidence of PI cover at levels well above the MTC minimum. A firm that cannot produce a certificate showing £5 million or £10 million is excluded from work, often without being told why.
The top-up market is more competitive than the primary market. Because top-up insurers do not carry the first £2 million or £3 million of every claim, their loss ratios are structurally lower and their pricing per million of limit declines as the firm goes higher up the tower. The price per million in the £8-10 million layer is typically a small fraction of the price per million in the primary.
The mechanical relationship between primary and top-up is governed by attachment, follow-form and limit erosion.
Attachment. The top-up policy attaches at the primary limit. So a £3 million-excess-of-£2 million top-up policy responds to losses between £2 million and £5 million. The primary must be exhausted first — the top-up insurer is entitled to refuse to engage until the primary has been paid in full on the claim.
Follow-form (or not). Most top-up wordings say they follow the form of the underlying primary. In solicitors’ PI this is usually expressed as “subject to the terms, conditions, exclusions and limits of the underlying primary policy”, with carve-outs. The follow-form principle means the top-up generally engages on the same coverage trigger as the primary. But it is not the same wording: the top-up is not contractually MTC-bound, and the SRA Participating Insurer’s Agreement does not bind the top-up insurer. The top-up insurer agrees to follow the primary as a matter of contract, not regulation.
Costs treatment. This is the most important wording difference. Under MTC clause 4 the primary policy pays defence costs in addition to the primary limit. Top-up policies are typically “costs-inclusive” — defence costs erode the top-up limit as well as the loss itself. So a £6 million claim with £900,000 of defence costs against a £2 million primary and £5 million top-up will eat into the top-up’s £5 million in a way the primary’s £2 million is protected against. Brokers should be alert to this and either negotiate costs-in-addition wording at higher layers (sometimes available, sometimes only at significant premium) or model the costs erosion explicitly when sizing the tower.
Drop-down and innocent insured. Some top-up wordings include “drop-down” features where the top-up policy provides cover at lower attachment points if the primary fails — for example on insurer insolvency. The innocent insured wording at top-up level often replicates the MTC clause 7 protection but should be checked, particularly where the top-up insurer is not a UK PI specialist.
Aggregation. The top-up policy’s aggregation provisions need to match the primary’s. Because the MTC clause 2.5 wording is in the primary, and the top-up follows form, aggregation will generally be assessed at primary level — but firms should not assume this. Inconsistent aggregation language between layers is one of the more dangerous tower structuring errors.
Section 11 of the Insurance Act 2015 applies to top-up wordings as it does to primary, protecting the insured against declinature for breach of terms not relevant to the actual loss. Section 3 fair presentation also applies — the firm has to disclose to the top-up insurer the same matters it discloses to the primary, plus any specific information the top-up insurer asks for in respect of higher-layer risk.
Consider an 8-partner firm with £4.5 million of fee income — 60% residential conveyancing, 25% commercial property, 15% private client and family. The firm holds a £2 million primary on MTC terms, with a £3 million top-up (taking the tower to £5 million) and a further £5 million layer (taking the tower to £10 million). All layers are with established UK PI insurers.
A new-build development claim crystallises against the firm: 70 plots conveyanced by a junior fee earner under one supervising partner, with a systemic failing in the title diligence process. Total loss claim £5.6 million; defence costs ultimately £800,000. Aggregation under MTC clause 2.5 treats this as one claim.
The primary pays £2 million of loss; defence costs are paid in addition under clause 4. The first top-up engages and pays £3 million of loss (taking the tower payout to £5 million on loss). The second top-up engages and pays £600,000 of loss, plus £800,000 of defence costs which erode that layer (the second top-up wording being costs-inclusive). Total recovery to the firm under the tower is £5.6 million of loss plus £800,000 of costs through the structure. The firm pays its excess on the primary, has £4.4 million of headroom remaining on the £10 million tower, and survives a claim that would have been catastrophic at minimum limits.
Start by mapping the firm’s actual exposure, not its peer benchmark. The right tower for a firm doing high-volume residential conveyancing is not the same as the right tower for a firm doing a handful of large corporate transactions. Ask the broker to identify the firm’s single largest exposure — by single matter, by client concentration, and by aggregation under MTC clause 2.5 across the work programme. Confirm lender panel minimums for every lender the firm acts for. Ask the broker to model costs erosion across the full tower at a representative claim size, and to show where the tower’s effective limit (after costs) sits. Check the follow-form provisions in every top-up wording, with particular attention to dishonesty exclusion language, innocent insured protection, and aggregation. Finally, ask whether the top-up insurers have committed to drop-down on primary insolvency or have any meaningful safeguards if the primary insurer exits the market mid-period.
Apex’s view: Top-up is where the bulk of meaningful risk transfer happens for any firm above the smallest end of the market, and it is also where the most expensive wording mistakes get made. The MTC does not reach above the primary. Costs-inclusive wording at top-up level can hollow out a tower in a single complex defence. We push hard on costs-in-addition at as high a layer as the market will give it, and where it is unavailable we model what the tower actually delivers — not what it nominally totals. Buying tower limit is meaningless unless the buyer knows what the tower actually pays.
Apex Insurance Brokers serves UK professional services firms and commercial businesses. Call 0117 325 0027, email hello@apexinsurancebrokers.co.uk, or request a quotation.
Get a quote