The woman building the rails ASEAN's banks were too slow to lay

Grace Tan keeps a screenshot on her phone that she shows to investors when she wants to end a conversation about whether her company is necessary. It is a remittance receipt from 2019: S$500 sent from a Singapore bank to a relative's account in Manila. The receipt shows it took four business days, lost S$31 to fees and an opaque exchange-rate margin, and required two phone calls to confirm it had arrived.

"This is what regional banking actually looked like for a normal person," Tan said, sliding the phone across the table at her company's office in a converted shophouse near Tanjong Pagar. "Not for a corporate treasury moving fifty million. For a domestic worker sending money home. Four days. Thirty-one dollars. And I helped build the systems that did that, which is why I take it personally."

The company she founded in 2022, Lattice Pay, now settles cross-border transactions across six ASEAN currencies in seconds rather than days, at a fraction of the cost. It processed US$4.1 billion in volume last year, more than tripled its revenue, and — in the development that prompted this interview — recently signed two of the regional banks Tan once worked for as clients of its settlement infrastructure.

Inside the machine she left

Tan spent eleven years in regional transaction banking, the unglamorous engine room where money actually moves between institutions. She rose to run cross-border product for a major Southeast Asian bank, a job that gave her an intimate, frustrating view of why the system was so slow. The answer, she learned, was not technology. It was correspondent banking — the chain of intermediary banks that a payment must hop through to cross a border.

Each hop adds a day, a fee and a point of failure. A payment from Singapore to Jakarta might route through a bank in Singapore, a correspondent in the United States holding dollars, a correspondent in Indonesia, and finally the recipient's bank. The money does not fly direct. It is relayed, and each relay takes its cut and its time. The system was built in the era of telex and never fully rebuilt.

"I sat in meetings for years where we agreed the correspondent model was broken," Tan said. "And then we did nothing, because fixing it meant rebuilding the rails, and no single bank could justify that capital expense for a problem every bank shared. It was a classic collective-action failure. Everyone suffered; no one would pay to fix it."

The bet on plumbing

Lattice Pay's insight was to build the missing layer as a neutral utility rather than as a bank. Instead of hopping payments through correspondents, the company pre-positions liquidity in each market — holding balances in local currency in each country it serves — and nets transactions against those pools. A Singapore-to-Manila payment never crosses a border in the literal sense; Lattice debits one pool and credits another, settling the imbalance separately and in bulk.

It is an old idea — netting and pre-funding — executed with modern infrastructure and, crucially, the regulatory licences to do it legally in each jurisdiction. Those licences are the moat. Tan spent the company's first eighteen months and most of its seed round acquiring payment institution authorisations across six countries, an unglamorous slog that competitors underestimated and investors initially questioned.

"Everyone wanted me to ship product. I spent a year and a half filling out licence applications," Tan said. "But the licences are the company. The software is the easy part. Anyone can write the software. Not everyone will sit through eighteen months of compliance reviews in six languages."

The strategy has aged well. As regulators across ASEAN push their own real-time payment linkages — the cross-border QR and instant-transfer schemes connecting national systems — Lattice positioned itself not as a competitor to those public rails but as a settlement layer that banks and the schemes themselves can use. When the central banks built the on-ramps, Tan had already built the bridge underneath.

Why the banks are calling

The two regional banks that signed with Lattice this year did so for a reason Tan finds quietly satisfying: they could not build it themselves fast enough, and the regulators were applying pressure to cut remittance costs that the correspondent model could not meet. Rather than rebuild their own rails, they are renting hers. It is the outcome she predicted in those frustrating meetings a decade ago, arriving from the outside because it could not arrive from within.

There is risk in this. A startup providing settlement infrastructure to banks is a startup that regulators will scrutinise like a bank, without the balance sheet of one. Lattice holds customer and pre-funded liquidity across six jurisdictions, each with its own rules about safeguarding, capital and reporting. A failure in any one market could cascade. Tan knows this, and talks about it more readily than most founders talk about risk.

"We are systemically boring on purpose," she said. "I do not want Lattice to be exciting. Exciting payment companies end up in the newspaper for the wrong reasons. I want us to be the most tediously well-capitalised, over-licensed, conservatively-run plumbing company in the region. That is the brand. Plumbing that never floods."

The competition closing in

Lattice is not alone. The region's instant-payment linkages threaten to commoditise exactly the service it sells, and well-funded rivals — including a Jakarta-based competitor backed by an Indonesian conglomerate and a Hong Kong player with mainland connections — are pursuing the same banks. Stablecoin-based settlement, still regulatorily fraught, lurks as a longer-term disruptor that could make pre-funded pools look quaint.

Tan is unbothered by the public rails — she expects to interconnect with them — and watchful of the stablecoin threat. "If a regulated, fully-backed stablecoin settlement layer arrives and the central banks bless it, that changes our cost structure," she conceded. "I would rather we build that layer than have it built against us. We are running experiments. I will not pretend the moat is permanent. Moats never are."

What she is really building

Press Tan on the ambition behind the plumbing and the banker's caution drops for a moment. Her grandmother, she says, spent decades as a domestic worker in Hong Kong, sending money home to the Philippines through exactly the slow, expensive channels that the 2019 receipt on her phone records. The thirty-one dollars lost on a five-hundred-dollar transfer is not an abstraction to her. It is family arithmetic.

"There are maybe forty million people in this region sending money across a border every month, and almost none of them are corporates," she said. "They are workers, families, small traders. The system charged them the most and served them the worst because they had no leverage. If Lattice does one thing, I want it to be that the next generation's receipt says seconds, and one dollar, and arrived."

Lattice is raising a Series C that people close to the company say could value it north of US$2 billion — a number that would have been unthinkable for a settlement-plumbing startup five years ago. Tan will not confirm it. She slides the 2019 receipt back into her pocket, the unanswered argument she carries with her, and says only that the work is maybe a tenth done. The rails ASEAN's banks were too slow to lay are finally being laid, by someone who watched them fail to do it.