MOBILE contracts are going up for millions, but there is a simple way to cut your costs by as much as £300 a year.

If you're on the wrong type of contract for your actual usage you could be wasting precious pennies - and a quick call to your provider could help cut your costs.

It comes as O2 and Virgin Mobile are hiking bills by as much as £48 a year from April.

BT, EE and Vodafone are planning bill hikes of up to £74 a year come April, too.

Meanwhile, millions of Three mobile customers will have to pay up to £31 extra a year, following changes in just over a month's time.

But a common mistake users make when taking out a phone contract is not knowing their usage needs - and most end up paying for more data than they need.

Typically texts and calls will be unlimited anyway - though you should always check as it can vary between contracts.

But unlimited data can makes your bills even more expensive - especially if it's wasted every month.

On the pricier end of the scale, some unlimited data contracts can cost up to £35.

That's the case for GiffGaff's unlimited , while Vodafone's costs from £30.