When is my S-Corporation Tax Return Due? ShareWhen is my S-Corporation Tax Return Due? S-Corporation returns are due March 15th each year. An automatic 6 month extension is available. Frequently Asked Questions - Business Taxes5 Steps To Take Before You Prepare Your TaxesAre Employers Required To Report The Information That Employees Claim On Their Form W-4 To The Irs?Can I Deduct My Home Office On My Business Tax Return?How Do I Choose The Right Accounting Software For My Business?Do I Have to File Taxes If My Business Made No Money?Do I Need To Make Quarterly Estimated Tax Payments?Need An Employer Identification Number (EIN)?