Taxpayers can find out if they owe back taxes to the Internal Revenue Service by visiting their local IRS office or calling 800-829-1040, as of 2015, notes the IRS. Phone service is available from Monday to Friday between 7:00 a.m. and 7:00 p.m. in each time zone.
The IRS does notify taxpayers on past due accounts and lists the amounts that individuals owe, states the IRS. It is possible to pay taxes with a debit or credit card, electronic funds transfers, a check or a money order. If a taxpayer is unable to pay his past due taxes, he can request a payment plan by filing the Installment Agreement Request, Form 9465, with the IRS.
Taxpayers can submit an Online Payment Agreement if they owe less than $25,000, explains the IRS. Taxpayers may still qualify for an installment plan if they owe more than $25,000 but must submit Collection Information Statement, Form 433F. It takes the IRS about 30 days to respond to an installment plan request. If the IRS approves the plan, they impose a $105 fee. The fee is reduced to $52 if the taxpayer sets up automatic payments from his bank account. Taxpayers can also reduce the amount of taxes owed by adjusting their W-4 to increase the amount of taxes withheld from their paychecks.