I have completed my tax return on HMRC website but I need to submit a SA109 form, can I use GoSimpleTax?

I have completed my tax return on HMRC website but I need to submit a SA109 form, can I use GoSimpleTax?

If you are required to complete the SA109 form, you must use a third party software for the FULL return and you can't make 2 separate submissions - any HMRC guidance on this is incorrect.

If you were to submit your return on HMRC and then file the SA109 separate, you would overwrite the previous submission (the one with all your details on) when you make the second submission.

Please do not submit the HMRC version and ensure you complete all details on a third party software.

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