The short answer

Search for "USAA SWIFT code" and you mostly find one code: IRVTUS3NXXX. It does not belong to USAA. USAA's instruction sheet for receiving an international wire names it as the SWIFT BIC of the intermediary agent, The Bank of New York, 225 Liberty Street, New York, NY 10286 (USAA, PDF). The money goes to BNY first, and BNY passes it to USAA.

So a sender who types only IRVTUS3NXXX and your USAA account number has not given enough. BNY also needs to know which of its customer banks the money is for, and which account there.

The fields, as USAA lists them

Field on the sender's form	What USAA says to enter
SWIFT BIC	IRVTUS3NXXX
Intermediary agent	The Bank of New York, 225 Liberty Street, New York, NY 10286
Creditor agent (the receiving bank)	USAA Federal Savings Bank, 10750 McDermott Freeway, San Antonio, TX 78288
Creditor agent account number (USAA's account at BNY)	8900624744
Creditor account	Your USAA checking or savings account number
Creditor name / remittance information	The full name of the USAA account holder

Source: USAA, PDF. USAA's sheet says "creditor" for the person being paid and "agent" for a bank. If the sender's form asks for a "beneficiary bank" and a "beneficiary", match them to the creditor agent and the creditor.

Loans and credit lines use other sheets

USAA publishes separate instruction sheets for a wire into a consumer loan account (PDF) and into a home equity line of credit (PDF). The loan sheet is not the deposit sheet with a different number. The creditor account becomes an internal USAA account (93627154050), and your loan number goes in the remittance information (USAA, PDF). Use the sheet that matches the account the money is for.

Currency and rate

A wire sent in a foreign currency is converted to US dollars by the intermediary bank or another institution before USAA gets it, and your account is credited in dollars. USAA says it cannot give an exchange rate for incoming wires (USAA, PDF). If you need to know the dollar amount, ask the sender to send US dollars from their side.

Fee, cut-off and weekends

Point	USAA's sheet
USAA fee to receive	None. The sending institution may charge its own
Cut-off	5:00 p.m. Central Time, Monday to Friday. Later wires are applied the next business day
Weekends and federal holidays	Wires are not processed

Check the code yourself

Paste IRVTUS3NXXX into the format checker. It splits into IRVT (the institution), US, 3N and the branch XXX, the primary office. The checker shows the shape only. It cannot show that the code belongs to BNY and not to USAA. That part comes from USAA's sheet. For other banks, see US bank SWIFT codes. For the other fields a sender abroad asks for, see receiving an international wire.