Luminescent metal halides have attracted considerable attention in next‐generation solid‐state lighting because of their superior optical properties and easy solution processibility. Herein, we report a new class of highly efficient and dual‐band‐tunable white‐light emitters based on Bi3+/Te4+ co‐doped perovskite derivative Cs2SnCl6 microcrystals. Owing to the strong electron‐phonon coupling and efficient energy transfer from Bi3+ to Te4+, the microcrystals exhibited broad dual‐band white‐light emission originating from the inter‐configurational 3P0,1→1S0 transitions of Bi3+ and Te4+, with good stability and a high photoluminescence (PL) quantum yield of up to 68.3 %. Specifically, a remarkable transition in Bi3+‐PL lifetime from milliseconds at 10 K to microseconds at 300 K was observed, as solid evidence for the isolated Bi3+ emission. These findings provide not only new insights into the excited‐state dynamics of Bi3+ and Te4+ in Cs2SnCl6, but also a general approach to achieve single‐composition white‐light emitters based on lead‐free metal halides through ns2‐metal ion co‐doping.

All-inorganic lead-free perovskite-derivative metal halides have shown great promise in optoelectronics, however, it remains challenging to realize efficient near-infrared (NIR) luminescence in these materials. Herein, we report a novel strategy based on Te 4 + /Ln 3 + (Ln = Er, Nd, and Yb) co-doping to achieve efficient NIR luminescence in vacancy-ordered double perovskite Cs 2 ZrCl 6 phosphors, which are excitable by a low-cost near-ultraviolet light-emitting diode (LED) chip. Through sensitization by the spin-orbital allowed 1 S 0 ! 3 P 1 transition of Te 4 + , intense and multi-wavelength NIR luminescence originating from the 4f!4f transitions of Er 3 + , Nd 3 + , and Yb 3 + was acquired, with a quantum yield of 6.1 % for the Er 3 + emission. These findings provide a general approach to achieve efficient NIR emission in lead-free metal halides through ns 2metal and lanthanide ion co-doping, thereby opening up a new avenue for exploring NIR-emitting perovskite derivatives towards versatile applications such as NIR-LEDs and bioimaging.