What UPI taught us about shared rails

A shopkeeper in Indore keeps one printed QR code by the till. A customer with an account at one bank pays from one app. The next customer has an account at a different bank and uses a different app. Neither payment needs the shopkeeper to know anything about either bank.

Stop and think about how odd that is. Nobody at the till signed anything with those banks, and nobody at those banks knows the shop. It works because everyone agreed, in advance, on how a payment is asked for and answered.

What UPI is, as far as we can check

India's government describes UPI as a system that powers multiple bank accounts into a single mobile application, from any participating bank. A government economics reference page, Arthapedia on ies.gov.in, says NPCI conducted a pilot launch with 21 member banks on 11 April 2016, and that it became officially operational on 25 August 2016. Both pages were read on 12 October 2026.

NPCI describes itself, in a press release dated 10 September 2026, as the umbrella entity that operates retail payment and settlement systems in India. It says the Reserve Bank of India and the Indian Banks' Association established it, and that it was incorporated as a "Not for Profit" company. UPI is among the products it lists.

One number, for scale. Reuters reported on 1 September 2026, citing NPCI's figures, that UPI handled about 24.51 billion transactions in August. The copy we read is on Ada Derana. We haven't checked it against NPCI's own statistics page, which wouldn't load for us.

That's the end of what we're sure of. Everything after this is opinion.

Why we think it worked

Here's our reading, and you should treat it as one.

First, UPI wasn't a bank's product. It came from a body set up by the central bank and the banks' association, so no single bank held the pen. A smaller bank and a large one could plausibly look at the same rules and see the same terms.

Second, we understand that anyone who wanted to take part had to follow the same written procedures. We haven't read NPCI's procedural guidelines ourselves, so this is our understanding and not a finding.

Third, and this matters most to us, the thing being shared was narrow. UPI didn't make banks identical. They kept their customers, their apps and their branding. What they shared was the answer to one question: how does one app ask another bank for money, and how does the bank reply?

The shared part was small, and every participant could see it. That, in our view, is what makes a rail a rail.

Carrying it over to agents

Now swap the shopkeeper for a hospital desk. Requests arrive from AI agents built by dozens of companies. The desk would like to know who stands behind each one, and it would like to know without calling every vendor.

If every company keeps its own list, the desk needs a separate arrangement with each. If one company keeps the list for all, then every other company depends on a competitor's goodwill. We went through that problem at more length in Why an agent registry has to live outside any one company.

The shared rail's answer is to share only the narrow question. Who is the individual, company or institution behind this agent, and what do the agent's details say? Companies keep their own products and their own agents. They agree on one place to ask.

NPCI is reportedly building a registry of its own for agents that pay through UPI. We wrote up what is known and unknown about that in What NPCI's agent registry means, and what it leaves open. It's reported, not published, and it's about payments.

Where the comparison breaks

It breaks in several places, and we'd rather say so than hide them.

Saakshya is not NPCI. We have no relationship with it, and it hasn't endorsed us. We're not a regulator either, and no regulator has asked us to exist. UPI came from NPCI, which the Reserve Bank and the banks' association had established. We're a non-profit still being set up, not yet incorporated, with no members and no board.

Money is also a tidier thing to move than trust. A rupee is a rupee. Agents act in health, tax, lending and government services, and no single authority covers all of those. A payments rail has one natural set of participants, the banks. An agent rail would have hospitals, tax offices, lenders and platforms, and they don't yet share a regulator or a habit of working together.

And UPI succeeding doesn't show that our approach will. A good analogy can still lead you to the wrong plan. All it tells us is that this shape, a neutral body and public rules and one narrow shared question, has worked once in India for a different job.

We'd add that what Saakshya plans is also narrower than a payments operator. It is being set up to register the individual, company or institution behind each agent, check their documents and the agent's details, and issue the agent an identity. Checking an agent's identity works offline, through an SDK. That's the whole of it for now.

What we don't know

We don't know whether the rail comparison will help or mislead. Maybe agents need something quite different, and we'll only find out by talking to the offices that receive their requests.

We don't know the full terms on which banks and apps take part in UPI. We've relied on NPCI's own description and on government reference pages, and we haven't read the detailed procedures.

We don't know who would write the rules for a shared agent rail, or how a disagreement between members would get settled. We have ideas, none of them decided.

And the date has a wrinkle. The 11 April 2016 launch was a pilot, and the public go-live was in August of that year. When people say UPI launched in April, they mean the pilot.