Delta's published loyalty ladder tops out at Diamond Medallion, but above it sits something you can't apply for: Delta 360, an annual, invitation-only membership for a tiny slice of Delta's biggest spenders. Of the invitation-only tiers at America's three big airlines — American's Concierge Key and United's Global Services being the others — Delta 360 is believed to be the rarest, with an estimated 5,000 to 10,000 members.

There's no published checklist for getting in. Delta says invitations go to a very small percentage of Diamond Medallions based on overall flight activity, purchases of premium cabins (Delta One, Premium Select, First) and spending on Delta SkyMiles Amex cards. Frequent-flyer watchers estimate you'd likely need $100,000 or more per year in Delta ticket spend if you're based at a Delta hub like Atlanta, Detroit or New York — and even more, since competition is fiercest there. Being based in Dallas or Newark, where American and United dominate, makes an invite notably easier. Spending your way in via credit cards alone would reportedly take millions. You also can't ask for it; Delta simply contacts you.

One guaranteed path exists: fly five million lifetime miles on Delta and you get Delta 360 for life through the SkyMiles million miler program.

So what do you actually get? More than you might expect, though less than the competition on paper. Members receive a dedicated 24/7 phone line with Delta's best agents (genuinely valuable during cancellations), a Sky Club Executive Membership worth $1,495 a year, and access to Delta One Lounges — widely considered the best lounges in the US — at JFK, LAX, Boston and Seattle when flying in Delta First same-day. There's also a shot at Porsche tarmac transfers at eight hub airports, a complimentary CLEAR+ membership ($219 a year), and the infamous Delta 360 bag tags, which have fetched hundreds of dollars on eBay. Boarding is only Zone 2, same as Diamond, and upgrades don't get a boost — it's not even a formal tier, so members still qualify for Medallion status separately.

Is it worth chasing? Almost certainly not deliberately. Unlike American's Concierge Key, which stacks lounge guesting privileges on top, or United's Global Services, Delta's version offers fewer documented perks, and the unpublished criteria mean the same flying might earn it one year and not the next. The real value is the soft treatment: proactive rebooking help and service that goes beyond the rulebook. Road warriors flying frequent domestic routes benefit most; someone taking a few long-haul business trips a year gains little beyond what Diamond already provides.

For ordinary travellers, the takeaway is simple: Delta's loyalty program now rewards spend over miles flown, and its true top tier is a quiet,unadvertised club. If you're pouring serious money into Delta tickets anyway, it's a nice surprise. Otherwise, Diamond Medallion — 28,000 qualifying dollars per year — is the ceiling worth planning around.