Yvert et Tellier is a postage stamp dealer and a philatelic publishing company founded in 1895 in the northern French city of Amiens, where the head office is still located. The logo is a circle divided into a snowflake and a smiling sun. It is a pun on the name of the company: hiver, été liés ("winter, summer together") sounds a lot like the French pronunciation of Yvert et Tellier.
The family company was founded by Eugène Yvert in 1831 as a printing works for a legitimist newspaper. The switch to philately was decided 1895 by Eugène's grandson Louis Yvert and his chief printer Théodule Tellier. Nowadays the company is still run by the Yvert family.