What is an Insurance Endorsement?

An insurance endorsement is a written change to an insurance policy that adds to, removes or alters the cover, terms or details in the original contract. It forms part of the policy and, where the change affects the risk, usually comes with an additional or return premium.

This guide is for underwriters, policy administration teams, MGAs and brokers. It covers how endorsements relate to mid-term adjustments and riders, the common types, how premium is recalculated, what an MGA can endorse under delegated authority and why manual endorsement processing causes problems.

What an endorsement is

A policy is agreed at inception on the facts known at the time. During the policy period those facts change: a business moves premises, buys a vehicle, takes on staff or adds a new activity, and the cover needs to follow. An endorsement is the document that records the change and makes it part of the contract.

Endorsements can be issued at inception or during the policy period. At inception they tailor a standard wording to a particular risk, for example by adding a clause that applies only to that insured. Mid-term they amend the cover in force. In both cases the endorsement takes precedence over the standard wording to the extent the two conflict, which is why endorsements are read alongside the schedule and the wording.

Each endorsement normally states the policy it amends, its effective date, what changes and any premium adjustment. The insurer, or the party administering the policy on its behalf, issues an updated schedule or endorsement document to the policyholder and their broker.

Endorsements, mid-term adjustments (MTAs) and riders: how the terms differ and where they overlap in UK usage

In the UK market the three terms overlap. A mid-term adjustment, or MTA, is any change made to a policy part way through its term. It describes the transaction: the request, the rerating, the premium adjustment and the reissued documents. An endorsement is the document or clause that records the change in the contract. Most MTAs therefore produce an endorsement, and UK practitioners often use the words interchangeably.

Rider is more common in US usage and in life and health insurance, where it usually means an optional benefit added to a base policy, such as a critical illness rider on a life policy. In UK general insurance the word is rarely used, and the same thing would normally be called an endorsement or an optional extension.

Common types with examples

Adding cover is the most frequent type. A commercial combined policyholder who starts hiring out equipment might add a section for hired-in plant, and a property owner might add terrorism cover to an existing material damage section. Removing cover works the other way: a business that sells a building removes it from the schedule.

Changing the sum insured is common in property and business interruption, where values move with rebuild costs, stock levels and turnover. A retailer increasing stock ahead of a peak trading period may take a temporary increase in the stock sum insured for a fixed number of weeks.

Adding a vehicle or location covers fleet motor policies, where vehicles are added and removed throughout the year, and property schedules where premises are acquired or leased. On large fleets this can mean hundreds of endorsements on a single policy each year.

Changing the insured's details covers a change of name, address, trading activity or ownership, and adding a named insured or an interested party such as a lender. Some of these changes are administrative and carry no premium; others, such as a change of trade, can change the risk materially.

Standard wording clauses are pre-written endorsements applied to tailor cover. Examples include a minimum security clause on a property policy, a subsidence exclusion for a property in a known risk area, or a clause noting a lender's interest. Each is drafted once and attached to the policies that need it.

How endorsements affect premium: additional premium, return premium and pro-rata calculation

When an endorsement increases the risk, the insurer charges an additional premium. When it reduces the risk, the insurer allows a return premium. Purely administrative endorsements usually carry no adjustment, although some insurers and brokers charge a fee.

The usual method is pro rata: the difference between the old and new annual premium is charged or returned in proportion to the time left on the policy. Take a policy with an annual premium of £1,200 and a change that increases the annual premium by £300, effective with 182 of 365 days remaining. The additional premium is £300 multiplied by 182 divided by 365, which is £149.59.

Insurance Premium Tax applies to the adjustment as it does to the original premium. HMRC's guidance on Insurance Premium Tax sets a standard rate of 12% and a higher rate of 20% for travel insurance and some insurance sold with appliances and motor vehicles. At the standard rate, the £149.59 additional premium in the example carries £17.95 of IPT. HMRC also requires insurers to keep the credit and debit notes or other documents that show an increase or decrease in premiums due, which in practice means every endorsement with a premium effect.

Other bases also apply. Some policies use short-period rates for cancellations, some apply a minimum premium that limits any return, and some classes, such as fleet motor and stock declarations, adjust premium at the end of the period against declared figures instead of at each change. The policy wording and the insurer's rating rules decide which basis applies, and the system issuing the endorsement has to apply the right one.

Endorsements under delegated authority: what an MGA can endorse within its authority and what must be referred

Under delegated authority, an MGA's power to endorse comes from the same agreement that lets it bind cover. Most binding authority agreements allow the holder to issue endorsements that keep the policy within the agreed classes, territories, limits, wordings and rates. Adding a vehicle to a fleet policy within the agreed rating guide, or correcting an insured's address, falls inside that authority.

Changes that would take the policy outside the agreement must be referred to the insurer before they are made. Typical referral triggers include a sum insured increase that breaches the per-risk limit, a change of trade into an excluded or referable activity, a new location in a territory outside the agreement and any change to wording that the agreement does not permit. The insurer's underwriter reviews the change, and the MGA issues the endorsement only once it is approved.

Every endorsement with a premium effect also has to appear on the next premium bordereau, so the insurer can see the change in exposure and reconcile the premium. An MGA that endorses outside its authority, or fails to report an endorsement, creates the kind of breach that delegated authority audits are designed to find.

Endorsements across jurisdictions and product variations

Insurers and MGAs that write in several countries, or offer several versions of the same product, face added complexity. Tax rates differ by territory, so an endorsement on a policy covering locations in more than one country may need premium split by location and taxed at different rates. Some jurisdictions require specific wording or language in policy documents, and some changes require local regulatory notification.

Product variations add a similar burden at home. An MGA might run several versions of a product for different distribution partners, each with its own rates, wordings and permitted endorsements. The endorsement process has to apply the right rules for each product version, which is difficult to do reliably when the rules sit in rating spreadsheets and procedure documents.

Why manual endorsement checking causes errors and backlogs

In many firms an endorsement still passes through several hands. A broker emails a request, a technician rekeys it, an underwriter checks it against the authority, someone calculates the premium in a spreadsheet and someone else produces the documents. Each handover is a point of delay and error.

The errors are familiar: the wrong effective date, a pro-rata calculation on the wrong number of days, IPT at the wrong rate, a clause omitted from the reissued schedule, or an endorsement that breached authority because nobody checked the limit. Errors in premium flow through to billing and to the bordereau, where they surface weeks later as reconciliation differences.

Backlogs follow from volume. Renewal season and fleet business can generate endorsement requests faster than a manual team can process them, and the policyholder may be uninsured for a vehicle or location until the change goes through. The administrative cost of an endorsement can also exceed the premium it generates, which is why some firms set minimum adjustment amounts below which no premium is charged or returned.

How software supports endorsements

Endorsements are largely rules-based, which makes them suited to automation. The system needs to hold the product's rating rules, wordings, authority limits and premium basis as configuration, so that each change is processed by the same rules every time.

In practice that means a broker or policyholder can request a change through a portal or API, the system rerates the policy, calculates the additional or return premium on the correct basis with the right tax, checks the change against the MGA's authority and either issues the endorsement and updated documents in one step or sends it to the insurer as a referral. The premium adjustment passes to billing and finance, and the change appears on the next bordereau automatically.

Genasys handles endorsements in its policy administration module, applying product rules and authority checks and issuing recalculated premium and documents together. For background on how these systems are structured, see our article on the basics of policy administration systems and our glossary entry on policy administration software.