50% increase in rent where agreement explicitly says increase by inflation

[leed1985]

Nearly 50% rent increase with 2 young children help - need someone who knows the law surrounding this / knows their stuff

The tenancy agreement explicitly says I quote word for word “the rent will be reviewed annually and periodically increased by the rate of inflation”

The rent is £650 (was advertised at 625 but we volunteered to pay an extra 25 from the start to help secure the property), we’ve been here 2 years and it has never been increased yet or even discussed.

They have proposed via phone to increase it to £960. It’s a 2 bed terraced - there are others in the general area going for around £700-800, only 3 beds are going for that amount and some still less.

Because the tenancy explicitly says increased by the rate of inflation, can I categorically go back to them and say you can only increase it by 3% or whatever the current inflation is right now?

Surely there is no way they can increase it by 50% if the clause says by the rate of inflation. They’ve committed themselves in contract - right?

[PallasAthena]

The clause seems clear, go back and quote it and ask them to give you their calculation of the rate of inflation.

There is some ambiguity in the clause IMO. Although the rent review is annual it isn't stated explicitly how far back the the rate of inflation can be taken into account, just "periodically". The Landlord could argue they are entitled to increase it by the rate of inflation since the rent was last set. So if that was say February 2022 (as you've been there two years) the rate of inflation (RPI measure) from Feb 2022 to Feb 2024 is 18.9%.

Does the lease have any other clause dealing with eg exceptional circumstances which could be used to justify a higher than inflation increase?

Is there any definition of 'rate of inflation' or anything saying which inflation index will be used or how inflation will be calculated?