422.91  Credit for estimated tax.
  Any amount of estimated tax paid is a credit against the amount of tax due on a final, completed return, and any overpayment of five dollars or more shall be refunded to the taxpayer with interest, the interest to begin to accrue on the first day of the second calendar month following the date of payment or the date the return was due to be filed or was filed, whichever is the latest, at the rate established under section 421.7, and the return constitutes a claim for refund for this purpose. Amounts less than five dollars shall be refunded to the taxpayer only upon written application in accordance with section 422.73, and only if the application is filed within twelve months after the due date for the return.
  In lieu of claiming a refund, the taxpayer may elect to have the overpayment shown on its final, completed return for the taxable year credited to the tax liability for the following taxable year.
[C79, 81, §422.91; 
81 Acts, ch 133, §3, 4
; 
82 Acts, ch 1180, §5, 9
]
89 Acts, ch 251, §28