D.C. Mun. Regs. tit. 14, r. 14-308
For purposes of this chapter, the term "security deposit" shall mean all monies paid to the owner by the tenant as a deposit or other payment made as security for performance of the tenant's obligations in a lease or rental of the property.
On or after February 20, 1976, any security deposit or other payment required by an owner as security for performance of the tenant's obligations in a lease or rental of a dwelling unit shall not exceed an amount equivalent to the first full month's rent charged that tenant for the dwelling unit, and shall be charged only once by the owner to the tenant.
All monies paid to an owner by tenants for security deposits or other payment made as security for performance of the tenant's obligations shall be deposited by the owner in an interest bearing escrow account established and held in trust in a financial institution in the District of Columbia insured by a federal or state agency for the sole purposes of holding such deposits or payments.
All monies held by an owner on February 20, 1976 for security deposits or other payments covered by this section shall be paid into an escrow account within thirty (30) days.
The owner of more than one residential building may establish one (1) escrow account for holding security deposits or other payments by the tenants of those buildings.
For each security deposit or other payment covered by this section, the owner shall clearly state in the lease or agreement or on the receipt for the deposit or other payment the terms and conditions under which the payment was made.
The housing provider shall post in the lobby of the building and rental office at the end of each calendar year, the following information: Where the tenants' security deposits are held and what the prevailing rate was for each 6-month period over the past year. At the end of a tenant's tenancy, the housing provider shall list for the tenant the interest rate for each 6-month period during the tenancy.
The provisions of this section shall not be applicable to Federal or District of Columbia agencies' dwelling units leased in the District of Columbia or to units for which rents are Federally subsidized.
D.C. Mun. Regs. tit. 14, r. 14-308