In the UK, the rules and regulations regarding rental increases are primarily governed by the terms of the tenancy agreement and the applicable laws. Here are some key points to consider regarding rental increments in the UK:

1. Assured Short-hold Tenancies (ASTs): For ASTs, which are the most common form of tenancy for private rented accommodation, landlords can generally only increase the rent once a year, and they must give tenants at least one month's notice of the increase.

2. Rent Act Tenancies: Different rules may apply to older tenancies known as Rent Act Tenancies. These tenancies may have their rent regulated by the Rent Act 1977, and specific rules apply to rent increases for these tenancies.