President Trump promised to keep his businesses out of his presidency. But taxpayers are already footing part of the bill for the Trump Organization's business trips.

In January, Eric Trump took a business trip to Uruguay. As the president's son, he gets Secret Service protection.

The Washington Post found it cost nearly $100,000 to provide the Secret Service with the rooms and support they needed to keep him safe.

Eric Trump visited the Trump Tower Punta del Este. The Trumps don't actually own the tower, but they licensed their name to it for between $100,000 and $1 million.

Since President Trump has refused to divest of his companies like past presidents, that means taxpayers just paid for part of a business trip that the president will probably profit from.

9 PHOTOS First Family: Getting to know Eric Trump See Gallery First Family: Getting to know Eric Trump Eric Trump is President-elect Donald Trump's third child with his first wife Ivana Trump. Caption: Ivana Trump, Eric Trump, her former husband Donald Trump and her daughter Ivanka Trump in 1998. (Getty) Eric attended The Hill School, a strict boarding school in Pottstown, Pennsylvania. Caption: Ivana Trump and Eric Trump in 1996. (Getty) Eric attended Georgetown University in Washington D.C. He is the only one of the adult Trump siblings that did not attend their father's alma mater University of Pennsylvania. Caption: Donald Trump Jr., Ivanka Trump, Eric Trump and Tiffany Trump (Reuters) Eric is a reality tv star just like his father. He has made appearances alongside the president-elect on The Apprentice as a boardroom judge from 2010-2015. Caption: Donald Trump (C) and his sons Eric F. Trump (L) and Donald Trump Jr. (R) attend the 'Celebrity Apprentice All Stars' Season 13 Press Conference in 2012. (Getty) Eric Trump married his wife Laura in 2014. She is a producer for CBS' Inside Edition. Instagram caption: "Amazing that our anniversary is also Election Day! Happy anniversary @laraleatrump 🇺🇸🇺🇸" Eric founded the Eric Trump Foundation when he was 23-years-old. The charity aims at raising money for children at St. Jude Children’s Research Hospital. The organization's website says they have "donated and pledged nearly $30 million dollars to St. Jude." Instagram caption: "So proud of our @erictrumpfdn Road Scholar truck! It's dedicated to the children of @stjude" Eric runs the Trump Organization's golf courses. Since joining the organization in 2013, Eric increased the number of international golf courses from three to 17. Instagram caption: "Beautiful day to play at Trump National Jupiter @larayunaska" While speaking on the campaign trail in October, Eric Trump mistakenly introduced then-vice presidential candidate Mike Pence as the Governor of Illinois. Pence is the governor of Indiana. The 32-year-old chalked it up to a slip of the tongue. Caption: Vice President-elect, Indiana Governor Mike Pence (C) is greeted by Eric Trump (R), son of President-elect Donald Trump. (Getty) Eric made headlines on Election day after he tweeted a photo of his ballot while voting for his dad. The tweet was quickly deleted, but not before garnering over 3,000 retweets and over 8,000 likes. It is illegal in New York to share a photo of your election ballot. Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

SEE MORE: Conflicted: A Newsy Special Report

An ethics expert told the Post, "This is an example of the blurring of the line between the personal interest in the family business and the government."

Don't be surprised if something like this happens again. The Trump Organization has dozens of businesses all over the world. And since the president has refused to release his tax returns, we don't know how many conflicts there are.

12 PHOTOS Members of the Trump family See Gallery Members of the Trump family NEW YORK, NY - MARCH 26: Ivanka Trump and Jared Kushner are seen on March 26, 2016 in New York City. (Photo by Tal Rubin/GC Images) BRIARCLIFF MANOR, NY - SEPTEMBER 21: Jared Kushner and Ivanka Trump attends the 9th Annual Eric Trump Foundation golf invitational at Trump National Golf Club Westchester on September 21, 2015 in Briarcliff Manor City. (Photo by Bobby Bank/WireImage) BRIARCLIFF MANOR, NY - SEPTEMBER 21: (L-R) Vanessa Trump, Donald Trump Jr., Ivana Trump, Eric Trump, Lara Trump, Ivanka Trump and Jared Kushner attend the 9th Annual Eric Trump Foundation Golf Invitational Auction & Dinner at Trump National Golf Club Westchester on September 21, 2015 in Briarcliff Manor, New York. (Photo by Grant Lamos IV/Getty Images) NEW YORK, NY - MAY 04: Jared Kushner and Ivanka Trump attend the 'China: Through The Looking Glass' Costume Institute Benefit Gala at the Metropolitan Museum of Art on May 4, 2015 in New York City. (Photo by Axelle/Bauer-Griffin/FilmMagic) NEW YORK, NY - JUNE 16: (L-R) Eric Trump, Lara Yunaska Trump, Donald Trump, Barron Trump, Melania Trump, Vanessa Haydon Trump, Kai Madison Trump, Donald Trump Jr., Donald John Trump III, Ivanka Trump, Jared Kushner, and Tiffany Trump pose for photos on stage after Donald Trump announced his candidacy for the U.S. presidency at Trump Tower on June 16, 2015 in New York City. Trump is the 12th Republican who has announced running for the White House. (Photo by Christopher Gregory/Getty Images) NEW YORK, NY - JUNE 07: Jared Kushner (L) and Ivanka Trump attend the American Theatre Wing's 69th Annual Tony Awards at Radio City Music Hall on June 7, 2015 in New York City. (Photo by Mark Sagliocco/Getty Images) BEDMINSTER, NJ - OCTOBER, 25: In this handout image provided by Ivanka Trump and Jared Kushner, Ivanka Trump (R) and Jared Kushner (L) attend their wedding at Trump National Golf Club on October 25, 2009 in Bedminster, New Jersey. (Photo Brian Marcus/Fred Marcus Photography via Getty Images) Donald Trump, president and chief executive of Trump Organization Inc. and 2016 Republican presidential candidate, center, speaks as his sons Donald Trump Jr., left, and Eric Trump, right, listen during a caucus night rally in Las Vegas, Nevada, U.S., on Tuesday, Feb. 23, 2016. Trump's dominating victory in the Nevada caucuses pushes him further out ahead of his nearest competitors for the Republican presidential nomination, giving his unorthodox candidacy a major boost heading into Super Tuesday contests next week. Photographer: David Paul Morris/Bloomberg via Getty Images 20/20 - Donald Trump and his family - including wife Melania Trump and his children - sit down for an interview with ABC News' Barbara Walters in a special edition of 20/20 airing Friday, Nov. 20 (10-11pm, ET) on the ABC Television Network. (Photo by Lorenzo Bevilaqua/ABC via Getty Images) DONALD TRUMP, JR., IVANKA TRUMP, ERIC TRUMP, TIFFANY TRUMP, BARBARA WALTERS LONDON, ENGLAND - JULY 28: Marla Maples (L) and Tiffany Trump have dinner at Sumosan on July 28, 2014 in London, England. (Photo by David M. Benett/Getty Images) BRIARCLIFF MANOR, NY - SEPTEMBER 15: (EDITORS NOTE: Retransmission of #455504994 with alternate crop.) (L-R) Donald Trump, Ivana Trump, Eric Trump and Lara Yunaska attend The Eric Trump 8th Annual Golf Tournament at Trump National Golf Club Westchester on September 15, 2014 in Briarcliff Manor, New York. (Photo by Dave Kotinsky/Getty Images) NEW YORK, NY - APRIL 18: Donald Trump, Eric Trump and Lara Yunaska attend the New York Observer's 2013 Young Philanthropy event at PH-D Rooftop Lounge at Dream Downtown on April 18, 2013 in New York City. (Photo by Laura Cavanaugh/Getty Images) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

More from :

Trump Administration Puts Iran 'On Notice'

Most Americans Disapprove Of Donald Trump — In Record Time

Trump Businesses' Foreign Debt Could Be A Conflict Of Interest