The answer to your question depends on what boxes you checked on the 4506T form that grants lenders access to your tax documents. If you checked box 6C then you agree to allow the lender to access your tax returns and account transcripts. If you did not check this box then you only agreed to release your tax return transcripts for the prior two years. Either way, as long as you do not have an outstanding, unresolved IRS tax lien against you, the issue should not impact your ability to close your mortgage. Based on the information you provided you do not have an outstanding IRS lien against you and you are paying your back taxes according to a plan agreed to by the IRS. I would not raise the issue unless the lender does and then you can explain the situation and let them know you are current with your monthly IRS payments. You should be good to go to close your mortgage as it relates to this issue.