Northern Ireland Deposit Cap: One Month's Rent Maximum

The Cap That Catches Landlords Out

Since 1 April 2023, the maximum tenancy deposit a landlord can take in Northern Ireland is one month's rent. This came in under Section 4 of the Private Tenancies Act (Northern Ireland) 2022, inserted as Article 5ZC into the Private Tenancies (Northern Ireland) Order 2006.

The rule sounds simple. It is not — because one month's rent is not the same as four weeks' rent.

Calculating the Cap for Non-Monthly Rent

If you charge rent monthly, the cap equals your monthly rent figure. A tenant paying £800 per month means the maximum deposit is £800.

If rent is paid on any other cycle, the statutory monthly equivalent is the rent attributable to one day's letting multiplied by 30:

• Weekly rent: (weekly rent ÷ 7) × 30
• Fortnightly rent: (fortnightly rent ÷ 14) × 30
• Four-weekly rent: (four-weekly rent ÷ 28) × 30

A weekly rent of £180 produces a monthly cap of (£180 ÷ 7) × 30 = £771.42 when rounded down to the nearest penny. Four weeks' rent would only be £720. So a deposit of £720 is within the cap, but a deposit of £800 would be an unlawful excess of £28.58.

A four-weekly rent of £800 produces a monthly cap of (£800 ÷ 28) × 30 = £857.14 when rounded down to the nearest penny. A deposit of £900 on that cycle creates an illegal excess of £42.86.

Round down to the nearest penny. Always.

What Fits Inside the Cap

The cap covers all money held as security. That includes:

• The main damage deposit
• Any additional amount taken for pet damage — it cannot be a separate charge on top of the deposit
• Any holding payment that converts into the deposit when the tenancy agreement is signed

If a third party (a guarantor or parent) pays part or all of the deposit, the total still cannot exceed one month's rent. There is no exemption for third-party payments.

Genuine advance rent — money applied directly to contractual rent obligations — does not count as a deposit. But if you label something "rent in advance" while actually holding it as security against damage or default, the authorities will reclassify it as a deposit. Relabelling funds to dodge the cap is a regulatory breach.

What About Pre-2023 Deposits?

A deposit lawfully taken before 1 April 2023 that exceeded one month's rent was not retroactively made illegal — as long as the tenancy continued uninterrupted under its original terms.

If the first tenancy ends and a new tenancy is granted on or after 1 April 2023, any part of the old deposit that continues to be held in connection with the new tenancy is a statutory "retention" under Article 5ZD. The one-month cap applies to that retention, and any excess above the new tenancy's monthly rent is recoverable by the person who paid it.

For a deposit paid or retained on or after 1 April 2023, a later rent reduction can also put the deposit above the cap. If rent drops from £900 to £800 per month, a £900 deposit is £100 over the cap. Return the excess and update the scheme registration.

The Penalty for Taking Too Much

Taking a deposit that exceeds one month's rent exposes you to:

• A council-set Fixed Penalty Notice of up to £500
• On court prosecution, a summary fine up to £2,500; the court may order the excess repaid to the person who paid it

Getting the Calculation Right

The conversion formulas are straightforward, but a single arithmetic slip on a four-weekly or weekly cycle puts you in breach. Our Northern Ireland Tenancy Deposits guide includes the conversion worksheets with worked examples for every payment cycle, plus the variation protocol for when rent changes mid-tenancy.

See more Northern Ireland guides →