IDEA: Be honest with your external auditors. They help to determine your next tax bill.

Be honest and upfront with your external auditing firm.  You want them to trust you in order to get your required audit finished and the statements prepared normally for your bank’s  review (and owners).  The auditors work for you so do not delay getting them information so they can finish the audit and then prepare your tax returns.  Give them all of the information you can in order to maximize your deductions and minimize the ultimate final payment required for the year’s final tax return.