Tax Relief on SIPP Contributions

I pay income tax at a rate of 40%, but do not complete self assessment as my earnings are fairly stable. I intend to add some contributions to a SIPP and understand that the provider will claim 20% tax relief directly. Is there a process to claim the other 20% tax relief outside of completing self assessment?

Hi,
You can see guidance here:
Tax on your private pension contributions
Thank you.