When you complete your Idaho state tax return, you may need to report certain taxes that aren't automatically included elsewhere on your return. The most common additional taxes are use tax on untaxed purchases and any penalty or interest for filing or paying late.
Additional Taxes on an Idaho Return
Use Tax on Mail Order and Internet Purchases
Idaho charges a use tax on taxable items that you purchased without paying Idaho sales tax and then used, stored, or consumed in Idaho.
This tax commonly applies to purchases made through:
- Online retailers
- Mail-order catalogs
- Out-of-state sellers
- Marketplace transactions where Idaho sales tax wasn't collected
The use tax rate is the same as Idaho's sales tax rate. If you bought taxable items during the year and no sales tax was charged at the time of purchase, you may need to report and pay use tax on your Idaho return.
Keep in mind that most purchases that qualify for an Idaho sales tax exemption are also exempt from use tax.
Penalty and Interest for Late Filing or Payment
If you're filing your Idaho return after the due date and you owe tax, Idaho may assess:
- A late-filing penalty
- A late-payment penalty
- Interest on any unpaid tax balance
You can enter these amounts on your return and pay them when you file. Doing so may help reduce additional interest that could continue to accrue on any unpaid balance.
How to Report Additional Taxes in the Program
To enter additional taxes on your Idaho return:
- Go to State
- Select Edit next to your Idaho return
- Open Additional Taxes
- Enter any applicable:
- Non-taxed purchases (mail order or internet purchases)
- Penalty amount
- Interest amount
What Information Will I Need?
Before entering these amounts, gather:
- Records of online or out-of-state purchases that were not charged Idaho sales tax
- Any penalty or interest amounts calculated by the Idaho State Tax Commission, if applicable
- Documentation showing the tax balance you owe
Where Can I Learn More?
For additional details about Idaho use tax, penalties, and interest, review the Idaho State Tax Commission guidance available here:
Idaho State Tax Commission Information Guide
Understanding these additional taxes before filing can help you avoid surprises and ensure your Idaho return is complete and accurate.