What Sixt unlocks

Most of what Sixt status unlocks resolves in a single match; only one path keeps going into a second program. Sixt Diamond, the top tier, matches straight into Hertz President's Circle, itself Hertz's top tier — free, but you can only claim it once every five years, and the matched status runs out on December 31 of the second calendar year after Hertz approves it. Sixt Platinum alone is enough for Avis President's Club, also Avis's top tier: you email proof of your Sixt status to Avis, and the match holds for about a year.

The same Avis match is also the first leg into Enterprise Plus, whose entry-level Platinum tier you reach by uploading your matched Avis card once you're in President's Club — two matches deep from Sixt Platinum, running through the US and Canada. It's the lowest-rank finish of the three, and keeping it past the first year means either running the Avis match again or hitting 24 rentals or 85 rental days a year on your own. For a one-time errand, the direct Hertz and Avis matches are the better deal; the Enterprise route only pays off if you're already renting enough to requalify on volume.