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Still have tax due in a few days...
How does the US tax system work? Does a business pay at the start of the new year, and citizens pay in April?
Most citizens have their taxes taken at source every pay period. The fortunate few who make money "investing" will have to cough up some more tax money by the deadline or face interest and penalties on any amount owing. Ditto for the unfortunate many who have second jobs and/or side gigs which don't extract enough tax-at-source because they haven't included the income from your other job(s) in their calculations.