[RPG] Do you add Proficiency bonus AND the stat modifier to skill rolls


I know this basic knowledge, but I seemed to have missed this info in the player's manual.

Say someone makes an stealth check: do I add their Dexterity modifier and their proficiency bonus in Stealth to the roll? In other words, does the Dexterity modifier apply to all Dex-related skills, including ones with a proficiency?

Best Answer

Whenever a PC makes what 5e calls an Ability Check, such as Dexterity(Stealth), they roll a d20, add their Ability Score Modifier, and their Proficiency Bonus if they are proficient with that skill. A PC Proficient in Stealth would add their Dexterity Modifier as well as their Proficiency Bonus.

This information is in Chapter 7: Using Ability Scores. It starts on p. 173 of the PHB(or p. 57-59 in the Basic Player Rules), and describes how a PC's Ability Scores come into play during the game, namely Ability Checks, Attack Rolls, and Saving Throws. The Chapter details some of the things you can do with the Ability Checks as well.