President Donald Trump and first lady Melania Trump are donating a total of one million US dollars (£766,000) to a dozen organisations involved in Harvey relief work.
The White House said charities including the American Red Cross, the Salvation Army and Habitat for Humanity would benefit from the money.
The American Red Cross and Salvation Army will each receive 300,000 US dollars (£230,000) while Samaritan's Purse and Reachout America will collect 100,000 US dollars (£77,000) each.
The Trumps are giving 25,000 US dollars (£19,000) each to eight other good causes: the American Society for the Prevention of Cruelty to Animals, Catholic Charities, Direct Relief, Habitat for Humanity, Houston Humane Society, Operation Blessing, Portlight Inclusive Disaster Strategies and Team Rubicon.
The money would come from the president's personal funds, the White House added.
The Gulf Coast of Texas was battered by Harvey when it made landfall on August 25 as a Category 4 hurricane and was later downgraded to a tropical storm.
Up to 50 inches of rain fell in Houston and surrounding areas with homes and roads being left underwater for days.
"Our hearts are heavy with sadness for those who lost everything," Mr Trump said at an event in North Dakota to pitch his plan for overhauling the tax code.
"They've also filled us with hope," he said, speaking of having witnessed the "unyielding strength and resilience of the American spirit".
White House spokeswoman Lindsay Walters said the Trumps saw some of these groups in action while visiting with hurricane survivors, emergency responders, volunteers and government officials during their visits to the region.
The American Red Cross said it is "grateful to the Trumps for their generous support of our mission".
The White House first said last week that Mr Trump wanted to make a donation, and sought suggestions from journalists on where he should contribute.
"He would like to join in the efforts that a lot of the people that we've seen across this country do," White House press secretary Sarah Huckabee Sanders told reporters last week, two days after Mr Trump first visited post-Harvey Texas.
"And he's pledging a million dollars of personal money to the fund," Mr Sanders said "And he's actually asked that I check with the folks in this room, since you are very good at research and have been doing a lot of reporting into the groups and organisations that are best and most effective in helping and providing aid, and he'd love some suggestions from the folks here."
Mr Trump met with three relief groups - the American Red Cross, Southern Baptist Relief and Salvation Army - in the Oval Office last Friday.