20 C.F.R. § 416.1902
For purposes of this subpart-
Authorization means your written permission, in a form legally acceptable to us and to the State from which you received interim assistance, for us to withhold the appropriate SSI benefit payment and send it to the State.
Interim assistance means assistance the State gives you, including payments made on your behalf to providers of goods or services, to meet your basic needs, beginning with the first month for which you are eligible for payment of SSI benefits and ending with, and including, the month your SSI payments begin, or assistance the State gives you beginning with the day for which your eligibility for SSI benefits is reinstated after a period of suspension or termination and ending with, and including, the month the Commissioner makes the first payment of benefits following the suspension or termination if it is determined subsequently that you were eligible for benefits during that period. It does not include assistance the State gives to or for any other person. If the State has prepared and cannot stop delivery of its last assistance payment to you when it receives your SSI benefit payment from us, that assistance payment is included as interim assistance to be reimbursed. Interim assistance does not include assistance payments financed wholly or partly with Federal funds.
SSI benefit payment means your Federal benefit and any State supplementary payment made by us to you on behalf of a State (see subpart T of this part) which is due you at the time we make the first payment of benefits or when your benefits are reinstated after suspension or termination. Advance payment, as defined in § 416.520 , payment based upon presumptive disability or presumptive blindness, as defined in § 416.931 , or certain payments made under the administrative immediate payment procedure, are not considered SSI benefit payments for interim assistance purposes.
State for purposes of an interim assistance agreement, means a State of the United States, the District of Columbia, or the Northern Mariana Islands. For all other purposes (for example, payment, appeals, notices) State also means a political subdivision of any of these.
We, Us, or Our means the Social Security Administration.
You or Your means someone who has applied for or is already receiving SSI benefits.
20 C.F.R. §416.1902