All TTartisan products (lenses, light meters, and adapter rings( are currently 12% off only at the official TTartisan online store -they offer both APS-C and full-frame lenses for Nikon Z-mount. This promotion is valid until the end of the month.
7artisans also has a 12% sale – they offer both APS-C and full-frame lenses for Nikon Z-mount.
Some Viltros mirrorless lenses are also on sale (5%~15%Off).
Venus Optics also has a special promotion on their Laowa macro lenses available only in the USA at Adorama and B&H Photo. This promotion includes several Nikon Z and F mount lenses and will expire on May 16th. Here are the details: