Serbinski Accounting Firms

I helped file someone's Federal taxes about a month ago for 2023. He did not file an extension. He underpaid a total of $386 which he paid when he filed online. His total tax for 2023 was $2,903 ($2,507 was paid via W2). He just got a notice from the IRS that he owes a penalty on the $2,903 of $395 ...