Discussion
It is important to note that the filing deadline for S corporations and partnerships is due on March 15. Only basic information is needed to file an extension and a tentative tax total. The tentative tax should be based on a conservative estimate of what a taxpayer expects their income tax liability to ultimately be. Although the extension provides a taxpayer with an extension of time to file, it does not provide an extension of time to pay. The entire income tax liability will be due with the extension.
References
https://www.irs.gov/pub/irs-pdf/f7004.pdf