How to switch from married filing separately to jointly

[cyclotron]

Wife has filed 2020 taxes as married filing separately. I have not filed my return yet. Now we want to file as married filing jointly. Deadline is today.

What should we do?

Should I file an extension?

Should I file my return as also married filing separately and then amend my return to jointly? My return is more complicated.

Anyway to withdraw her filed return and file jointly? 

[ColeenD3]

You can amend her tax return from Married Filing Separately to Married Filing Jointly and include your information. There is no way to cancel her return, you must correct/amend it.