Reselling News: A $500 Million Resale Subsidy War and Amazon's December 18 Return Label Rule

Somebody finally put a dollar figure on why buyer shipping keeps getting cheaper on the apps you sell through. That is the first item. The second is a return rule that starts costing Amazon sellers money in six weeks, and the third is a postage change that went live while you were asleep.

ThredUp says rivals may spend $500 million buying buyers

On ThredUp's third quarter call on November 4, chief executive James Reinhart estimated that competing peer-to-peer resale platforms could spend as much as $500 million on marketing and order subsidies in the second half of 2026 alone, with shipping subsidies on top of that. He called the spending "wholly irrational," per Value Added Resource's write-up of the call. He also said that "the minute that these companies pull back on marketing, growth slows, churn ramps up," and pointed at Vinted as where budget-conscious shoppers are heading, with some of the shift going to Depop.

I covered ThredUp's soft holiday guidance here on Friday. The guidance was the symptom. This is the diagnosis, and a rival's own filing supports it. eBay's quarterly report for the period ended September 30 shows sales and marketing expense of $747 million against $606 million a year earlier, and attributes the gap mostly to a $120 million increase in marketing program costs "primarily related to Depop and eBay Live," per the 10-Q filed with the SEC.

What to do: treat a subsidized channel as rented traffic. The 99 cent buyer shipping and the free promotions are budget lines that somebody reviews every quarter, and ThredUp's chief executive just told investors he expects them to get cut. Work out what your margin looks like on each platform at normal shipping, keep listings live in more than one place, and do not let this quarter's sell-through on a subsidized app set what you are willing to pay at the thrift store.

Amazon requires prepaid return labels starting December 18

This one is not a this-week announcement. Amazon's notice went out in October, and I have not covered it here. It matters now because the date is about six weeks out and it lands in the middle of holiday return season.

Starting December 18, 2026, US returns on seller-fulfilled orders will require a prepaid return label. Within seven calendar days of a return request you either upload or authorize a prepaid label through Manage Seller-Fulfilled Returns, or you refund in full without getting the item back, as PPC Land reported from the seller notice. A label sent through Buyer-Seller Messaging does not satisfy the requirement and does not stop the clock. Heavy and bulky items are excluded for now. If you do neither within the seven days, Amazon says it may issue a returnless refund and deduct it from your seller balance, and the buyer keeps the product, summarized here alongside the other Amazon deadlines landing before December 18.

What to do: return postage stops being a maybe and becomes a line in your cost per Amazon sale. Pick the item value below which you will simply refund and let the buyer keep it, because on a cheap unit the label plus the handling costs more than getting the thing back is worth. Write that number down before December 18, since a seven-day clock does not care how busy the week of Christmas is.

USPS rates moved this morning

The Ground Advantage and Priority Mail adjustment eBay flagged for November 8 is live as of today. I wrote it up yesterday, so the only update is that it has happened, and that it is the third postage change in about two weeks. Calculated shipping already caught up on its own. Any flat rate you typed in by hand did not.

The takeaway

Two of these three move money out of your pocket without ever sending you a bill. A subsidy ending is invisible until your sell-through sags, and a return label rule is invisible until the first week it eats a $14 item. The defense in both cases is the same boring thing: a current, per-platform number for what one sale actually costs you to complete.

Building that number for a real catalog takes an afternoon and saves a season. It is the sort of afternoon we spend together most weeks at The Income Lab.

Hero photo of a second-hand clothing shop in Prague by MAKY.OREL, CC BY-SA 4.0, via Wikimedia Commons.