Stablecoin Transparency Act This bill requires a stablecoin issuer to hold all reserves associated with each fiat currency-backed stablecoin they issue in (1) certain government securities; (2) fully collateralized security repurchase agreements, or (3) U.S. dollars or other nondigital currency. A fiat currency-backed stablecoin is a digital asset backed by a nondigital currency and is redeemable on a one-to-one basis in that currency. Each stablecoin issuer must publish monthly on their website a report on the reserves held by the issuer that has been audited by a third party.