ROSARITO, Mexico — At the sprawling beachfront Las Rocas Resort and Spa in the Mexican state of Baja California, the restaurant El Mesón serves up American-style pizza and Mexican seafood accompanied by a breathtaking view of the Pacific. To drum up more business, the restaurant is running a new campaign in local publications, with a limited-time offer.

Their advertisement shows a beaming, middle-aged couple, a silver-haired gentleman and a blond. Her arms are draped comfortably around his shoulders. “Super special!” reads the text over their heads, in English. “Seniors 50% off your check!” In the tiny print below, a disclaimer notes that the deal is available to those aged 55 and up.

That marketing focus is intentional. In 2017, for the first time in twenty years, Mexico topped the list of International Living’s annual ranking of the best places for U.S. citizens to retire. The population of Americans in Mexico is rising, in size as well as in age.

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Yet most of them may be there illegally. South of the border, it’s relatively easy for U.S. citizens to live without legal documentation. In fact, some official reports indicate that illegal Americans seem to be the rule, not the exception.

One 2015 study from Mexico’s National Institute of Statistics and Geography reveals that a stunning 91.2 percent of Americans in the country don’t have their papers in order. That figure includes typos and other minor irregularities, and doesn’t appear to account for dual nationals.

The welcome many American immigrants feel in Mexico stands in stark contrasts to the way their Mexican counterparts are treated by Uncle Sam.

At the border crossing into Tijuana from San Diego, Americans can drive straight into Mexico without stopping or showing any kind of identification.

Mexicans generally embrace Americans and the influx of U.S. dollars that accompany them, and the Mexican government rarely deports Americans — typically just for very serious crime. Fines related to immigration paperwork can range from $50 to a few hundred dollars.

Conversely, under the Trump administration, even those people who grew up in the United States, brought here as babies or children, are now being deported for lacking formal documentation.

“There is a great deal of irony there,” says Sheila Croucher, author of the book, “The Other Side of the Fence: American Migrants in Mexico.” She adds, “I believe the Mexican people are remarkably adept at separating the actions and attitudes of the U.S. government from that of the American people.”

According to the U.S. State Department, around a million Americans currently reside in Mexico. But that number is only an estimate, since citizens aren’t closely tracked leaving the U.S. For its part, Mexico struggles to tally incoming visitors.

“I think it’s safe to say that over the past few years there has been a marked increase,” Croucher says. “And there’s been no indication of a reverse flow of people coming back from the towns in Mexico where large numbers of Americans have settled.”

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Statistics from the U.S. Social Security Administration show that distributions to beneficiaries in Mexico increased 7.2 percent between 2012 and 2016. Yet those numbers, too, aren’t exactly reliable: many American seniors move south while keeping their old bank accounts back home.

Some of the 15,000 Americans skirt formal residency requirements by obtaining tourist visas, and renewing them every 180 days. Otherwise, a one-year temporary visa costs about $194 USD.

Cheap living, proximity and established enclaves of Americans are three top reasons why Americans are drawn to retiring in Mexico, says Jen Stevens, the executive editor of International Living.

“Part of the reason Mexico came out on top [in our ranking] is because of the dollar being so strong this year, compared to the peso,” Stevens says. “It is even more affordable now than it was a decade before.”

Hot spots for American immigrants, young and old alike, include cities and towns like San Miguel de Allende, Rosarito, the Valle de Guadalupe, Lake Chapala and Ajijic.

And with the climbing cost of healthcare in the U.S., some American retirees also view Mexico as a good option if assisted living facilities or in-home private care become necessary.

Scott Astorga of Palm Springs says he opened a small retirement home in Rosarito in June 2016. “There’s a demand here,” Astorga says. “That’s why I’m in business. It’s growing. Back in 2003, there weren’t any assisted living facilities.”

Yet some Americans find themselves unsettled by what still seems to be a fact of Mexican life: the “mordida,” or bribe.

Sean Gunderson, 57, of Arizona bought a beachfront second home in a gated community along the Tijuana-Rosarito coast in 2004.

A few years later, the former law enforcement consultant was advised to pay a bribe after the Mexican government refused to fix a typo on paperwork related to his property. The incident rankled Gunderson so much that he decided to put his house on the market, scrapping a plan to develop a multi-million dollar assisted living community in Baja California.

“If you don’t mind operating that way, as an American, you can buy influence and connections,” Gunderson says. “But for us, in terms of investing, that was the straw that broke our backs.”

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More American Retirees Head to Mexico, Some Illegally originally appeared on usnews.com