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The Daily Insight

What are the most common mistakes people make when filing their taxes?

Author

James Craig

Published Feb 22, 2026

The most common mistakes people make when filing their taxes are neglecting to include necessary information, according to Mark Jaeger, director of tax development at tax preparation firm TaxAct. Filers frequently forget to give correct routing numbers for their bank accounts or make an error when listing their Social Security numbers.

When to indicate income tax borne by employer?

Thus, do not indicate “Income Tax Borne by Employer” in the Form IR21. Tax is considered to be borne by employer if the employer is bearing the tax liability of the employee. The amount of tax liability will then form a taxable component in the hands of the employee. You need to indicate “Income Tax Borne by Employer” for such cases. 4.

What happens if you make a mistake on an invoice?

To correct a mistake (e.g. goods invoiced as standard-rated, which should have been exempt or zero-rated); Goods or services are accepted, but terms of the contract are not fully met (e.g. sub-standard goods are accepted by the customer at a reduced price); Discount given for a past transaction.

When to issue a simplified tax invoice instead of a regular one?

You may issue a simplified tax invoice instead of a tax invoice if the total amount payable for your supply (including GST) does not exceed $1,000. A simplified tax invoice only requires the following information:

When do you get your tax refund if you made a mistake?

If you’re due a refund, you can choose to apply it to the next year’s return or have a refund check mailed to you. To claim a refund, you typically must file your form 1040X within three years after the date you filed your original return or within two years after the date you paid the tax, whichever is later.

What happens if you make an arithmetic error on your tax return?

If the IRS notices an arithmetic error, for example, it’ll usually fix the oversight and notify the taxpayer. Most tax filing errors are innocent mistakes. Still, there are things you can do to reduce careless errors and improve accuracy.

What happens if I file my taxes wrong?

You can use a 1040-X to submit additional or updated information to the IRS and to attach another form to your tax return. Pay any additional tax owed as quickly as possible to avoid accruing interest. Tax returns are complex—some more so than others—and they’re easy to get wrong.

When to file an amended tax return if you made a mistake?

For other mistakes, like math errors or missing forms, the IRS will alert the filer or fix the problem for them, Coombes says. The deadline to file an amended return is about three years from the date you filed the original return.

What are the most common tax calculation errors?

Tax calculation errors were the most common mistakes reported by the IRS in 2017. This is a broad category that refers to many possible errors, including simple things like forgetting to include a source of income that you earned or accidentally transposing some numbers on your return.

What to do if you make a math error on your tax return?

The IRS will usually fix small, harmless math errors for you if it finds them. But if you notice that you made a big error, like forgetting to report income, you don’t have to wait for the IRS to come asking questions. You can fix the problem yourself by filing an amended tax return on Form 1040-X.