The American Red Cross is encouraging people to donate money on its website or to text 90999 to donate $10. The organization is also asking for volunteers.
Crowdfunding site Global Giving is attempting to raise $2 million for funds that will "exclusively support local relief and recovery efforts from this storm."
Airbnb has launched a site for people looking for a place to stay and for those who can offer shelter. Fees are waived for people who check in before September 1.
United Way of Greater Houston has set up a relief fund that people can donate to. The organization said its first priority is shelter and basic needs like food. The organization said it will also focus on long-term recovery efforts.
The Houston Humane Society is also available, with limited staff.
Comedian and actor Kevin Hart has challenged fellow celebrities to help Harvey victims. In the same spirit as the Icebucket Challenge, he pledged to donate $25,000, then tagged other celebrities and encouraged them to donate and tag others as well.
Texans star defensive end J.J. Watt posted an emotional video asking for fundraising assistance to help victims of the massive flooding that Houston is experiencing.
Apple is letting users donate to the American Red Cross directly on iTunes and App Store.
The fund passed the goal of $200,000 in the first two hours. Watt then tweeted that he was raising the fundraising goal to $500,000.
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