UPI Outage Attributed To Surge In API Calls From Banks, Says NPCI

The National Payments Corporation of India (NPCI) has stated that the UPI disruption on April 12, 2025, was a result of an unusually high volume of requests by some banks. The outage caused payments to fail in a number of apps, such as Google Pay, PhonePe, and Paytm, for a few hours.

This was the third disruption of this nature in just one week, and people began questioning the stability of the system, particularly at times of heavy use.

Reason Behind the Issue

Some payment service provider (PSP) banks were exceedingly using the "Check Transaction" API (application programming interface)—a facility to check if a transaction had been processed or not. These banks were issuing repeated calls to the system, including checks on transactions that occurred during previous days, without waiting for any feedback from the system.

This continuous stream of requests generated high traffic and led to congestion in the system. Consequently, numerous users attempting to make UPI payments between 11:40 am and 4:40 pm on April 12 experienced transaction failures or delays.

At this time, the success rate of UPI payments fell dramatically to approximately 50 per cent for nearly two hours and stayed at approximately 80 per cent for the subsequent three hours. UPI systems typically function with extremely high success rates, so this fall is a serious problem for users and businesses.

Temporary Fix and Future Plans

To put things in order, a temporary measure was implemented at 4:15 pm and regular success rates were resumed at 4:40 pm. As a matter of urgency, NPCI also directed the respective banks to cease the use of the "Check Transaction" API with immediate effect.

NPCI further said UPI has been developed to operate in an "active-active-active" mode in three locations, which normally means if any part of the system breaks down, others still function. However, with the sheer volume of API calls, the system's payment processing was impacted.

This event, and two prior ones in the same week, has compelled NPCI to explore more long-term solutions. It stated that it is developing more effective preventive measures to prevent similar disruptions in the future. These could involve improving the use of certain APIs by banks and establishing clearer rules on how often certain transaction checks can be issued.

For crores of people and businesses that rely on UPI for everyday payments, ensuring that the system remains reliable is critical. NPCI’s challenge now is to make sure such problems don’t repeat.