How Long Does an IRS Audit Usually Take? Well that can be a difficult question to answer and it's dependent on a lot to do with the taxpayers factual circumstances some taxpayers are bigger some are more complicated and some have a lot more to go through generally speaking of the IRS audit process shouldn't take all that long if you gather your information if you could substantiate the items that are on the return that. I'm meeting or - and the audit should be over with audits that taking longer than a few months are a red flag for me and the reason for this is it's a sign that the auditor is engaging in a fishing expedition you should come in with a clear plan of the audit you should present your material and if you do so clearly and cognizant ly there shouldn't be any issue for the auditor here's my return here's my substantiation now go home it really should be as easy as that. The problem is is that most taxpayers get audited have some sort of adjustment that the IRS is seeking to make so the important thing is understanding where your particular pain point is addressing that pain point as much as possible and then moving on quickly the longer the audit remains open. The more documentation that's provided to the auditor to greeter the risk so audits that go longer than four or five months are generally a negative sign to the taxpayer and need to be dealt with quicker.