In the era of e-commerce, fast, affordable delivery has never been more essential for retailers. On Thursday, representatives from the Package Coalition — a business alliance whose members include Zappos, Sorel and Amazon, along with the National Retail Federation (NRF) — held meetings with House and Senate staffers to express the reasons behind their opposition to price increases at the United States Postal Service.

“Our members who engage in e-commerce rely on affordable package delivery services, six days a week,” the NRF said in a panel presentation. “If the Postal Service is forced to raise prices, it will have an outsized impact on our members and the retail economy in general.”

USPS announced postage rate increases in October that are scheduled to go into effect on Jan. 27, including the largest-ever price increase for the cost of a stamp, a 10 percent jump to 55 cents. The Package Coalition argues that these excess costs disproportionately hurt small businesses and Americans living away from urban centers.

“In many remote and rural parts of America, the postal system is the only affordable alternative delivery system and serves as an economic lifeline for small businesses and consumers,” the group said in its invite to the briefing, adding that the postal service delivered more than 5.7 billion packages to 157 million addresses last year and employs 7.5 million Americans.

The group has also opposed many of the recommendations made by a task force put together by the U.S. Department of the Treasury, which include higher prices on commercial package deliveries. The report was commissioned after President Donald Trump criticized Amazon for “costing the United States Post Office massive amounts of money for being their Delivery Boy.” (The USPS, meanwhile, has argued that it doesn’t lose money on any of its shipping contracts.)

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