Business Partnership Income Tax Return – Prepare, document for review and e-file Form 1065 U.S. Partnership Income Tax Return including Schedule K-1 Partner’s Share of Income, Deductions, Credits, etc., and Form IL-1065 Partnership Replacement Tax Return and related extensions and estimated tax payments. Business S Corporation Income Tax Return - Prepare, process for review and e-file Form 1120S U.S. Income Tax Return for an S Corporation including Schedule K-1 Shareholder’s Share of Income, Deductions, Credits, etc., and Form IL-1120-ST Small Business Corporation Replacement Tax Return and related extensions and estimated tax payments.