Most Americans have their tax returns completed by paid preparers. The IRS issued a list of the top 10 errors made by paid preparers who complete Form 1040. Note that some of these errors resulted in additional taxes being paid by the taxpayer. The list is reproduced in a table here. It also can be used by taxpayers who prepare their own tax returns, since they often make the same mistakes. ErrorTax impact
| #1 Taxpayer identification numbers or names for dependents didn’t match IRS or Social Security records. | The IRS did not allow the exemptions. |
| #2 Spouse’s social security number (SSN) was either missing or didn’t match Social Security records. | Spouse’s personal exemption was not allowed. |
| #3 Taxpayer identification numbers or names for dependents didn’t match IRS or Social Security records. | All or part of the child tax credit was not allowed. |
| #4 Dependent’s last name had to be corrected. | none |
| #5 Earned income credit was figured or entered incorrectly. | Earned income credit was changed. |
| #6 SSN for children who qualify their parent or parents for earned income credit didn’t match Social Security records. | Earned income credit was changed. |
| #7 Did not include nontaxable earned income from W-2’s. | Earned income credit was changed. |
| #8 Primary SSN was incorrect or illegible. | none |
| #9 Child’s age exceeds the limit. | Child tax credit was reduced or removed. |
| #10 Based on information reported, the IRS refigured the tax using the filing status for a single person. | varies |
