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Amex has finally moved on from Costco, as evidenced by its strong results across the board in Q4 2017, which were announced at the firm’s quarterly earnings held late last week.

Following a two-year cost-cutting plan and months of investments and efforts to rejuvenate business, Amex is performing solidly, with increases in revenue, slight decreases in expenses, and multi-year highs in billings growth following a long downturn.

Vast improvements in US billed business, its largest segment, are likely propelling Amex’s comeback. The Costco cobrand portfolio comprised 8% of Amex’s $1 trillion billed business in 2015, leaving a massive loss for the firm to compensate for following the sale. That led to multiple quarters of decline or tepid growth in Amex’s US consumer segment.

But that’s now behind the firm, which saw 8% growth in US billed business in Q4 2017 — a stark contrast from the 14% decline Amex posted in the prior Q4, and even above the 6% growth it saw adjusted for Costco in that quarter. As Amex continues to refocus on adding new customers and increasing engagement among existing ones, as well as growing acceptance to give consumers more opportunity to spend on Amex, it’s likely that this growth will continue, ultimately helping Amex’s overall performance, especially as the firm works to grow internationally and in other segments.

It’s looking increasingly like redoubling on premium cards — the firm’s traditional bread and butter — could be what it’s needed to boost growth all along.

Premium cards soared in Q4 2017. Amex finished 2017 with its highest ever number of Platinum cardholders, seeing record spending among them, according to the firm’s earnings call. And those users are engaging with their cards beyond just spending on them — customers are using travel benefits, like lounge access, Uber, and free checked bags through some cobrands, more frequently than in the past. That’s a good sign for Amex’s premium offerings, and points to their success at engaging current consumers and bringing in new ones, which the firm needs.

Amex finished 2017 with its highest ever number of Platinum cardholders, seeing record spending among them, according to the firm’s earnings call. And those users are engaging with their cards beyond just spending on them — customers are using travel benefits, like lounge access, Uber, and free checked bags through some cobrands, more frequently than in the past. That’s a good sign for Amex’s premium offerings, and points to their success at engaging current consumers and bringing in new ones, which the firm needs. But Amex will have to work to keep it up in a changing environment. Popular premium cards can be a drain — Chase plans to cut about $200 million in costs from its premium card unit because of excessive costs. Amex isn’t immune to that, with costs related to both rewards and card member services rising in response to increased engagement with its pricier products. But the firm’s long-standing experience in the premium space could differentiate it from other entrants — Amex’s rewards spending is “normalizing” to a rate where it is more consistent with the firm’s billings progress, helping the firm keep pace with its growth. If the firm can leverage its brand recognition and continue to invest in and build out offerings that entice new types of customers to sign up and spend without overextending its capital, it might come out on top in the premium space, and in turn outperform even its own expectations following the Costco loss.

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