TPR says authorisation puts safeguards around master trusts by ensuring they are run by fit and proper people and have the right systems, processes, plans and finances in place.
The regulator revealed 30 applications had been submitted by master trusts seeking authorisation, three of which have already been approved.
A further 10 schemes were granted an extension and are expected to file an application in the coming weeks.
Nicola Parish, executive director of frontline regulation at TPR, said: “Passing the end of the application window is an important step towards a market of authorised master trusts which millions of pension savers can have confidence in.
“A number of applications have now been submitted and we are expecting more applications over the next few weeks from those schemes which have been granted an extension.
“We will now work to assess this large volume of applications and we are confident that we will process these applications within the timeframes laid out in law. We always expected there to be a peak in applications and have planned accordingly.
“We look forward to the authorisation of more master trusts in the coming months and will be maintaining a close relationship with them as part of our supervision work to ensure these standards continue to be met.”
All existing master trusts had until 31 March to apply for authorisation, trigger their exit from the market or request an extension to the application period.