A six-month spat between the world's largest retailer and the world's biggest credit card company is over, as Walmart has struck a deal with Visa that will see the latter's cards accepted at all of the chain's Canadian stores.

The two companies announced the agreement on Thursday, but made no mention as to what concessions were made by whom to end the dispute.

"Visa cardholders can once again use their Visa credit cards as a form of payment in all Walmart stores across Canada," Visa Canada spokeswoman Carla Hindman said in an email. Starting tomorrow, "Visa credit cards will be accepted at all Canadian Walmart stores, including in Manitoba and Thunder Bay, Ont."

Those two markets were singled out because they are the only locations thus far affected by Walmart's threat, made last June, to eventually stop accepting Visa cards at all of its stores. The move to drop Visa started at all three Walmart stores in Thunder Bay in July and then spread to all 16 stores in Manitoba in October.

At issue were so-called interchange fees, which credit card companies charge retailers as a cost for processing a transaction. Typically they are a percentage of the total value of goods sold, but different cards and different stores have different rates.

While consumers don't pay those fees directly, retailers pass on the costs to shoppers via higher prices.

Walmart had insisted that Visa's fees are too high, saying it pays more than $100 million a year for the service — far more than it pays for other cards, or other payment methods such as debit, which charges a flat fee per transaction. Visa, meanwhile, countered that it already gave Walmart one of its lowest interchange fees on all its cards.

Neither side was willing to disclose on Thursday what the new fee structure for Visa cards at Walmart will be, but data from research firm Value Penguin suggests the average interchange fee on Canadian credit cards is roughly 1.76 per cent. That's far higher than those in Europe, where fees below one per cent are the norm. The French average, for example, is just 0.21 per cent.

According to payment processing firm Moneris, as of April 2015, Visa's internal guidelines said their cards charged between 1.42 and 2.08 per cent in interchange fees, depending on the card used, at a standard retailer. Although the company would likely negotiate another deal with a customer the size of Walmart.

Mark Satov, strategy adviser at Satov Consultants, said the timing of the deal — right after the busy holiday shopping season — was likely significant.

"It's after Christmas and somebody looked at their numbers and said, 'It wasn't as strong as we thought,'" he said in an interview. "And my bet is it's Visa."

Satov suggested the card company had more to lose in the long run from feuding with a giant retailer such as Walmart. "People don't look for the best deal to find the cheapest TV or gadget or toy and then say, 'I'm not going there, they don't take Visa,'" he said. "That's not the way people think."

The card company also likely faced pressure from its banking partners to get a deal done, because Visa is a brand, but the payments themselves are processed by whatever Canadian bank has issued the card.

When it comes to which credit cards to issue to their customers, "the bank has a choice [and] if Visa is not accepted at one of the biggest retailers in the country, it's not attractive anymore," Satov said.