A federal tax extension can be filed without the taxpayer signing an authorization form as long as there isnu2019t any money due. That answer is for the law. The correct thing to do if the tax preparer expects to get the client to continue using him or her is to let the client know that an extension is going to be filed and why.I say u201cwhyu201d because there are a lot of people who donu2019t realize that all information should be on the tax return. Partnerships, S corporations, and trusts donu2019t always file on time. If you donu2019t have the K-1 from one of those, the personal return should be extended.