If the IRS determines that an employee does not have enough withholding, the IRS will notify an employer to increase the amount of withholding tax by issuing a “lock-in” letter that specifies the maximum number of withholding allowances permitted for the employee.
More from H&R Block
If the IRS determines that you are not withholding enough taxes from your pay check and each year you owe a substantial tax balance, the IRS can send a letter to your employer that requires them to withhold taxes at the highest rate of single with 0 exemptions. This is known as a lock-in letter. This letter sets the withholding rate your employer must use and it cannot be changed by filing a new Form W-4. The rate specified in the lock-in letter can only be changed with IRS approval.
Get help from an IRS expert
H&R Block’s experts can solve any IRS problem, no matter how complex.
Learn about the different options when you can't pay or still owe money from a past return from the tax experts at H&R Block.
Liens and levies are tools the IRS uses to collect back taxes. Learn more about each one -- and how to avoid tax liens and levies by working with the IRS.
The IRS grants four types of penalty relief, but many taxpayers don't ever ask. Learn how to request penalty abatement from the IRS.
Learn what to do when you can’t pay your taxes – to avoid these 10 consequences of tax debt. Get the facts from the tax experts at H&R Block.