definition of 90 day letter
90 day letter is an irs notice stating that there was a discrepancy or error within an individual s taxes and they will be assessed unless petitioned the taxpayer has 90 days to respond otherwise the audit deficiencies will result in reassessment also known as a notice of deficiency breaking down 90 day letteronce you receive your notice you have 90 days 150 days if the notice is addressed to a person who is outside the country from the date of the notice to file a petition with the tax court if you want to challenge the tax the irs proposed according to the agency these notices are usually sent after or audit in the case of people who fail to file a tax return or who have unreported income 