Defect-fluorite structured Eu3+-doped Y2Sn2O7 nanoparticles (30–40 nm) were successfully prepared through a facile co-precipitation method without any organic additives or templates followed by calcination in air. Luminescent properties of the as-prepared Y2-xEuxSn2O7 (0.02 ≤ x ≤ 0.6) nanophosphors were fully characterized from an experimental and theoretical point of view (excitation, emission, lifetime, critical concentration, temperature-dependent luminescence and thermal stability, type of interactions and the Judd-Ofelt analysis). The nanophosphors showed relatively sharp excitation bands from 360 to 530 nm and exhibited characteristic emission bands with the most intensive emission centered at 612 nm. In addition, Gd1.98Eu0.02Sn2O7 and Lu1.98Eu0.02Sn2O7 samples were prepared in order to study how substitution of RE3+ (Y3+ with Gd3+ and Lu3+ ions) influences on luminescent properties of RE1.98Eu0.02Sn2O7 and thermal stability of their luminescence. In order to understand better luminescent properties, the Judd–Ofelt analysis was applied to all the synthesized powders. The highest value of quantum efficiency, ~96%, was estimated for Lu1.98Eu0.02Sn2O7. To assess potential application in high-power LEDs, the temperature-dependent emission spectra of Y1.98Eu0.02Sn2O7, Gd1.98Eu0.02Sn2O7 and Lu1.98Eu0.02Sn2O7 nanophosphors were studied. Display omitted •Eu3+-doped Y2Sn2O7, Gd2Sn2O7, Lu2Sn2O7 samples were prepared by co-precipitation method.•An average size of all synthesized samples were ranging from 30 to 40 nm.•The highest value of quantum efficiency (QE~96%) was obtained for Lu1.98Eu0.02Sn2O7.•The color coordinates of studied samples are close to commercial red phosphor.•Samples showed good thermal stability in the range of operating WLED temperatures.