But his marquee Mar-a-Lago resort in Florida is not signed up, nor are his golf courses in Virginia, Philadelphia or Bedminster, New Jersey - where, The New York Times reported Thursday, some illegal immigrants have been working for years.
"We have tens of thousands of employees across our properties and have very strict hiring practices", Trump Organization spokeswoman Amanda Miller wrote in an email, without specifically addressing the article about Morales. "If any employee submitted false documentation in an attempt to circumvent the law, they will be terminated immediately".
"I'm using E-Verify on just about every job", Trump told MSNBC host Chris Matthews during a televised "town hall" in March 2016, later adding, "I'm using E-Verify, and I'll tell you, it works".
Trump has made border security a signature issue since he first began his presidential campaign on June 16, 2015, by saying: "When Mexico sends its people, they're not sending their best".
The Guatemalan said supervisors were aware of her immigration status and helped her keep her job after she crossed the border illegally in 1999. "We sweat it out to attend to his every need and have to put up with his humiliation", Morales told the New York Times.
Ms Diaz said she washed and ironed Mr Trump's white boxers, golf shirts, khaki pants, sheets and towels with special detergent in a separate machine.
The Times reports that Victorina Morales and Sandra Diaz cleaned at Trump's resort in Bedminster, New Jersey, for years despite not having proper documentation.
She said she is certain that her employers - perhaps even Trump - knew of her unlawful status all along.
Trump National Golf Club in Bedminster N.J. Julio Cortez AP
"After the family separation humanitarian crisis, the racist fear-mongering during the midterms, and the violent tear-gassing of children seeking asylum, it should come as no surprise that Trump executes his campaign of hate and division while profiting off the backs of undocumented and vulnerable workers", she said.
Morales told The Times that she understood she could be fired or deported by going public with her story.
The two are now considering a lawsuit against the Trump Organization for workplace abuse and discrimination.
Two women who cleaned rooms set aside for Trump at one of his golf resorts in New Jersey say they used false papers to get hired.
Romero has called for federal and state investigations into the matter.
'I ask myself, is it possible that this señor thinks we have papers? "He knows we don't speak English", Morales said.
Another former golf club worker who said she was undocumented said Mr Trump was "meticulous" and once raged over an orange stain on his white collar, which she said was his makeup.
A woman who makes Donald Trump's bed and irons his clothes undocumented immigrant, it has been revealed. "Why wouldn't he figure it out?"
Trump's Next Pick for UN Ambassador Is a Former 'Fox & Friends' Host
If her appointment is confirmed she will replace Ms Haley, who had held the role since November 2016. Nauert was "under strong consideration" for the post, but he was evaluating other candidates.
Trump to name former Fox anchor Heather Nauert as next United Nations ambassador
A Republican congressional aide said the president was expected to announce his decision by tweet on Friday morning. All the while, she stayed in the good graces of the White House, even as Tillerson was increasingly on the outs.
Andy Samberg and Sandra Oh to Host the 2019 Golden Globes
While First Man did manage a few nominations in the end, Steve McQueen's elevated heist thriller was passed over completely. That's all well and good for the Comedy side, but oh boy, the competition for the Drama category is going to be fierce.