While Reg. Z still applies, you are not required to disclose an APR (unless you have other finance charges).
226.18(e) footnote 42
"For any transaction involving a finance charge of $5 or less on an amount financed of $75 or less, or a finance charge of $7.50 or less on an amount financed of more than $75, the creditor need not disclose the annual percentage rate"
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