The largest donation in the second quarter came from Andrew Beal, a Texas-based banker who once squared off against Mr. Trump in a bankruptcy case. He donated $339,000 to Trump Victory.

The committee received $169,500 from the real estate developer Stanley Chera. Mr. Chera partnered with the company owned by the family of Mr. Trump’s son-in-law, Jared Kushner, on a $1 billion deal to sell the retail space at 666 Fifth Avenue in Manhattan.

The three Trump committees raised more than $17.7 million from the beginning of April through the end of June, the period covered in Sunday’s reports. That was the second-largest quarterly haul since he took office, though it was a drop of nearly $2.5 million from the preceding quarter.

The committees spent more than $8.5 million in the second quarter.

Some of the largest payments — totaling more than $2.4 million — went to the companies owned by Mr. Trump’s campaign manager, Brad Parscale, which specialize in online and email fund-raising. Mr. Trump’s campaign appears to be renting out its email list to other committees through Mr. Parscale’s firm, a not-uncommon revenue-generating technique used by committees that have built files of active supporters. Mr. Parscale’s firm has paid the campaign more than $236,000 in list rental income, the filings show.

The Trump campaign and its affiliated committees also spent heavily on merchandise, including the “Make America Great Again” hats that are the most recognizable branding of his campaign. The reports show nearly $600,000 worth of payments to an array of companies for hats, T-shirts, stickers, towels and commemorative coins to be given or sold to supporters.