Rental Security Deposit Calculator

Note that this interest rate calculation only applies to interest accruing on a security deposit under a residential lease or mobile home park rental agreement on or after January 1, 2015. Interest accruing on Maryland residential tenancies that have a start date on or before 12/31/2014 remain subject to the fixed 3% interest rate requirement for periods prior to 12/31/2014, except for residential tenancies in Prince George's County (please refer to local ordinances for details).

As of January 1, 2015, for all Maryland jurisdictions, the amount of interest a landlord or mobile home park owner must pay residential tenant upon return of the security deposit is the greater of the daily U.S. Treasury yield curve rate (“Constant Maturity Treasury”) for one year, as of the first business day of each year, or 1.5%.

The Maryland Department of Housing and Community Development provides this customized calculator that determines the interest due on a security deposit by allowing a user to enter a start date (the date on which the security deposit was given to the landlord), a tenancy end date, the county in which the residence is located, and the amount of the security deposit. Note that all inputs must be included to generate a result.

Interest is only payable on security deposits of $50 or more, and accrues at monthly intervals from the beginning of the tenancy. No interest is due or payable unless the landlord has held the security deposit for at least 6 months, or for any period less than a full month (which may happen at the end of a lease).

For information on the 2014 Maryland legislation that required the creation of this calendar, and the methodology of its calculations, go to Background & Methodology.

For more information on Maryland landlord/tenant laws and support available to resolve disputes, please refer to the Maryland Attorney General's Office, Consumer Protection Division at https://www.oag.state.md.us/consumer/landlords.htm

Also available is the downloadable ebook - Landlords and Tenants: Tips on Avoiding Disputes​, which provides valuable information on state law that these arrangements are subject to.​