Can I upgrade my zoho mail id to paid version

Can I upgrade my zoho mail id to paid version

Hi Team,

Iam using zoho mails which is in free version. One of my mail id storage is exhausted. Iam ready take a paid version but I want to do it only for one domain. Is it possible ?? I tried to check the option from my setting page but, I couldnt get any info on the same.

Please let me know the possibility

Thanks
Balaji