Hi , Can anyone tell me what is the reasonable relocation allowance in IT companies and do they have any tier level ranges?

It is approximately INR 1.5Lakhs, one-time.

We are SaaS company, we had 50k per employee across the org

it varies from org to org anything between 50k to 2Lakh as one time payment. few companies will pay immediately few will pay after 3 months

At one of the companies I worked (25+ years old company), we used to keep the relocation allowance equivalent to the hire's one moth gross pay. At my current company, we do anywhere between 30-60K.