Santander-Webster megadeal expected to ride the fast US bank deal approval wave

Banco Santander SA's proposed acquisition of Webster Financial Corp. is expected to receive a quick regulatory approval, with its preexisting US presence likely to outweigh the foreign ownership aspect.

Bank M&A deals have been closing faster under the new regulatory regime, including larger ones, but Santander's purchase of Webster is the largest deal the regulators will review yet, with a value of $12.23 billion at announcement, and involves a bank based outside the US buying one inside the US. Although that adds complexity and could create additional hurdles, Madrid-based Santander's existing US presence could provide a counterbalance, deal advisers said. Looking ahead, the market will be on the lookout to see if other foreign banks get inspired by this transaction and buy other US banks.

Santander is optimistic about its approval prospects, given the more conducive regulatory environment in the US. A Santander spokesperson told S&P Global Market Intelligence that the company's US bank is equally as American as other large banks that have made acquisitions and received quick approval.

Santander Holdings USA Inc. finished the third quarter of 2025 with $168.11 billion in assets, while Webster had $84.07 billion in assets at the end of 2025. Fifth Third Bancorp's purchase of Comerica Inc. closed in 119 days, and the buyer had $209.31 billion in assets, while the target had $78.04 billion in total assets, according to data in the last reporting period before the deal was announced.

In total, four deals involving bank targets with at least $25 billion in assets announced since the start of 2025 have been completed, and they have taken a median of 121 days to close, according to Market Intelligence data.

Setting closing expectations

Unlike many other banks that provide a specific quarter as the expected closing timeframe for their deals, Santander and Webster provided a broader timeframe of the second half of this year. If the deal closes at the beginning of the expected time frame, on July 1, that would be 148 days since the announcement, whereas if the deal closes at the end of the range, on Dec. 31, that would be 331 days.

If the deal were to close in the 121-day median, then it would close June 4, sooner than expected.

"It's a big window, but I think it's giving themselves a little bit of flexibility and not being pegged to the third quarter, for example, and then if they don't meet those expectations, creating some of that conversation of 'What if?' or 'What's going on?'" Matthew Veneri, head of financial institutions and insurance investment banking at Brean Capital LLC, said in an interview.

Moreover, Santander has a lot of M&A activity going on with its Webster purchase, its acquisition of London-based TSB Banking Group PLC and the stake sale of Santander Bank Polska SA.

"They've got their plate full" so they might be "being a little bit more vague on the timeline because there's nothing that they're hurrying up and looking to do immediately thereafter as well," Veneri said.

Puts and takes

Since Santander is based in Spain, the deal will require regulatory approval in the US and EU by both the Board of Governors of the Federal Reserve System and the European Central Bank. That could add some time to the closing timeframe, but ultimately, it should close in a timely fashion like other recent large US bank deals, advisers said.

The fact that Santander is already operating in the US through its Boston-based subsidiary, Santander Holdings USA Inc., bodes well for timely approval prospects, they said. Santander already has more than 370 branches in the US.

If "this was a new foreign buyer coming in, that might create a little bit of uncertainty, but given that they're currently operating, regulated in this marketplace, I think maybe a little bit of complexity, but [it's] not like it's going to be a huge, huge shift in timing," Veneri said.

Another tailwind for the deal is that the banks' branch maps are pretty much completely separate, avoiding challenges related to antitrust, said Michael Bell, partner and leader of Honigman LLP's financial institutions practice.

Douglas Weissinger, a member of the business services group advising financial institutions at law firm Butler Snow LLP, noted that the US losing a US-owned bank might give regulators some pause.

"That may make a difference, given that we are losing a US entity to a foreign entity. I certainly think that they would take that into account, and I think that this administration, in particular, would take that into account," Weissinger said in an interview. On the other hand, he added, already having domestic market presidents, executive officers and other employees could reduce hurdles for the transaction.

The specific foreign country in question is unlikely to raise issues with US regulators, another adviser said.

"I'm not aware of anything in particular that would lead me to believe that a bank that is headquartered in Spain would be the subject of any intense criticism from the current administration," a bank M&A lawyer with about 20 years of experience told Market Intelligence.

Other deals involving non-US banks

Other banks based outside the US might follow Santander and buy other US-based banks. These deals have been relatively rare, with only eight since 2020. Those deals also tended to be smaller, with a median deal value of $29.9 million at announcement, excluding the Santander-Webster deal.

London-based fintech Revolut Ltd. previously planned to buy a US-based bank but ended up changing plans to seek a charter of its own instead. But the acquisition approach could work for other banks based outside the US.

"You will see other foreign banks and foreign nonbanks, i.e., fintech and some others, which we've already started to see, pursue acquisitions of US-based banks," Veneri at Brean Capital said. "[Santander's acquisition of Webster] will be an interesting case study for those types of transactions."