The Tenancy Deposit Loan Scheme allows Civilian and Service personnel to apply for an advance of salary loan to help meet the cost of a deposit for a rental property in all UK locations. The initiative was developed by the Department of Communities and Local Government to assist you in meeting the cost of a deposit which can sometimes act as a barrier to moving. It is limited to the cost of the deposit and must be repaid over no more than 12 months.

https://www.gov.uk/government/news/help-to-secure-a-rental-home-the-mod-tenancy-deposit-loan-scheme