March and April remain the months when many broadband and mobile contracts become more expensive. But while the increases are still happening, the way they are calculated has changed significantly.
Until recently, many of Britain’s largest telecoms providers linked annual increases to inflation, typically adding a further percentage on top. A contract might, for example, have increased each year by the Consumer Prices Index (CPI) plus 3.9%.
That made the eventual cost difficult to predict when customers signed up. Inflation would not be known until months or even years later, meaning someone entering an 18 or 24-month broadband contract could not know exactly what they would be paying towards the end of it.
Ofcom changed the rules from 17 January 2025. Providers can no longer include inflation-linked or percentage-based price rises in new contracts. Any increases written into a contract must instead be clearly stated in pounds and pence before the customer signs up, along with when they will take effect.
The annual price rise, however, has not disappeared.
Ofcom’s latest pricing analysis found that in-contract increases announced for fixed broadband customers in 2026 ranged from £2 to £4 per month.
That means a household paying £25 per month could see its broadband bill rise to £29 following a £4 increase. Over a full year, that is an additional £48.
The change has therefore made broadband price rises more predictable, but not necessarily insignificant.
It also creates an unusual effect for customers on cheaper broadband packages.
A fixed £3 monthly increase represents a 12% rise on a £25 tariff. The same £3 added to a £50 package represents a 6% increase.
In percentage terms, customers starting with some of the cheapest broadband deals can therefore experience the largest increases.
Tharindu Fernando, co-founder of Full Fibre Broadband Deals, which tracks pricing across the UK broadband market, says customers increasingly need to look beyond the headline price when assessing the cost of a new contract.
“A £3 monthly increase doesn’t sound particularly large when you’re signing up, but that’s another £36 a year. On a £25 broadband package, it represents a 12% increase,” Fernando says.
“The important number isn’t necessarily what the service costs in the first month. With 18 and 24-month contracts, it’s increasingly useful to look at what you’ll actually pay across the entire minimum term.”
The new system represents a fundamental change from the inflation-linked model.
Before the rules changed, a customer might have known the formula behind a future increase but not the actual amount. Under the new system, someone signing a contract should be able to see in advance what their monthly payment will become and when.
Ofcom introduced the rules after concluding that inflation-linked increases left consumers carrying financial risk they could neither predict nor easily understand.
The regulator has stopped short of controlling how large contractual increases can be. Providers remain free to set their prices, including scheduled increases, provided the amount and timing are clearly disclosed under the applicable rules.
There is also still a legacy of the old system.
Contracts signed before 17 January 2025 may contain inflation-linked or percentage-based increases. This meant some customers continued to face increases calculated under the previous model during 2026, while newer customers were already moving onto fixed pounds-and-pence increases.
The transition is gradually working its way through the market as older contracts expire.
The wider picture is also more complicated than annual increases alone suggest. Ofcom’s latest research found that prices for many faster broadband products have been falling in real terms, while customers who are out of contract can often make substantial savings by switching or agreeing a new deal.
Its 2026 analysis found that in-contract customers typically paid less than those who had fallen out of contract. For standalone broadband and common broadband bundles, average savings for customers who were in contract ranged from £7 to £9 per month.
That makes the annual spring increase only one part of what households actually pay.
A customer whose bill rises by £3 per month may still have a competitively priced contract. Someone whose monthly price has not recently increased could nevertheless be paying considerably more if their minimum term has ended and they have moved onto an out-of-contract rate.
For consumers, the new pricing rules at least make one part of the equation easier to understand.
The old question was how high inflation might be when the next annual increase arrived. Increasingly, the relevant numbers are already sitting in the contract.
As another March and April approach, Britain’s annual broadband price rise has not vanished. It has simply become easier to see coming.
