O2 is set to push up the prices of its mobile tariffs for small and medium business customers by 2.7% from March.
All SMB O2 customers on the DISE billing system will be hit by the price rises as well as customers on bespoke pricing and those on RRP.
Only b2b customers on zero sub, O2 Lease and data only deals or those with a specific contract clause excluding them from any price increases while in contract, are exempt.
O2 has also introduced new terms for new or re-signing b2b customers making clear that O2 will change the price of their mobile tariff in April each year in line with the previous February RPI inflation rate.
O2 said that since Ofcom published guidance on mid-term price rises in fixed term contracts it has been seeking clarification from the watchdog on the implications of the guidance. It said Ofcom has now made clear that O2 and its partners have to be to be 'clear and transparent' about RPI price changes in all contracts in order to comply with the new regulations.
O2 dealers and distributors are being warned by O2 that they must make these inflation hikes clear to new and signing customers from 23 January to meet the new regulations.
The operator said rising inflation had forced it to introduce the price hikes on monthly contracts. In a statement to customers it said the move will allow the company to continue to invest in the O2 network, products and services.
A spokesman said: 'Price increases are never welcome but inflation has an impact on our costs. For most of our customers it will mean an additional charge of less than 60 pence on their monthly subscription. We continue to invest in our network and the services that matter to our customers while still offering great value for money.'