A holding deposit isn't the same as a security deposit. It's a smaller, upfront payment (capped at one week's rent) that you pay to take a property off the market while tenant referencing and other processes are completed. Once the tenancy is agreed, the holding deposit is either put towards your first month's rent, put towards your security deposit, or returned to you.
The Tenant Fees Act 2019 sets strict rules about holding deposits. The landlord or agent has a "deadline for agreement", which is 15 days from when you paid the holding deposit, unless both parties agree a different period in writing. If the tenancy isn't agreed within that deadline, the holding deposit must be returned to you in full.
There are only three circumstances in which a landlord can keep your holding deposit:
If a landlord refuses to return your holding deposit when they should, you can take the matter to the First-tier Tribunal, which can order repayment.
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