topic Oklahoma SCorp Program Caused me Penalty and Interest in Self employed

Oklahoma SCorp Program Caused me Penalty and Interest

BoydBob1 — Wed, 11 Feb 2026 09:44:30 GMT

The OK SCorp program (512-S) of the Turbo Tax Desktop Business program did not provide a way to enter and submit OW-8-P-SUP-C, which annualizes my business income over 4 qtrs, allowing me to avoid penalty and interest for underwithholding.

This is very disappointing and has caused me another $100 or so. OK requires efiling of the 512-S so I was stuck with that and being unable to incorporate the OW-8-P-SUP-C form in the filing.

Can a Turbo Tax admin look into this and get back to me ASAP?

Re: Oklahoma SCorp Program Caused me Penalty and Interest

KristinaK — Mon, 13 May 2024 16:01:36 GMT

TurboTax does not support Form OW-8-P-SUP-C.

To use the annualized income installment method to figure out the underpayment penalty, in Forms Mode, check the box on Form OW-8-P and manually enter the required annual payment on line 9 for each quarter. You will also need to attach manually filled out Form OW-8-P-SUP-C to your return and then file.

Re: Oklahoma SCorp Program Caused me Penalty and Interest

BoydBob1 — Thu, 16 May 2024 03:08:56 GMT

Kristina - I couldn't see how to attach the form to my efiling. If you're saying to attach the form to a filing that I mail in to Oklahioma - well Oklahoma requires 512-S to be efiled, so can't do that. Need Turbo Tax to add support for form OW-8-P-SUP-C

Re: Oklahoma SCorp Program Caused me Penalty and Interest

KristinaK — Thu, 16 May 2024 21:24:45 GMT

I have conveyed your message to the tech team. Thank you!