You'll receive a Form 1099-R Distributions From Pensions, Annuities, Retirement or Profit-Sharing Plans, IRAs, Insurance Contracts, etc. from the payer of your 401(k) distribution. A copy of that form is also sent to the IRS.
To enter the 401(k) distribution in your TaxAct return:
For additional information, see IRS Publication 575 Pension and Annuity Income.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the document at the time it is accessed.