Can A Wizard Use Chainmail To Cast Spells?

Any character who is proficient with a particular type of armor can cast spells while wearing that armor with no penalty. This is due to two primary reasons: there are better ways for mages to get a decent Armor Class, and to cast and maintain any spell, a Wizard must be both stationary and undisturbed by attack upon their person.

Anyone can wear any armor they want, but if they aren’t proficient in that armor, it will come with unpleasant consequences. For example, a wizard won’t be able to cast any spells if they put on chainmail, which negates the entire point of being a wizard.

At 1st level, the mage puts the armor on right after sleep is cast. By 3rd or 4th level, the character must remove their armor to cast a spell. The only kinds of armor that do not interfere with spellcasting are elven chain mail and elven plate mail.

When a spellcaster casts a spell using a slot that is of a higher level than the spell, the spell takes on the higher level for that casting. For instance, a Wizard can cast Magic Missile without needing a free hand to hold the symbol if it is being visibly worn.

In older editions, wizards couldn’t wear armor and cast spells, with rare exceptions like elven chain. In 3.x, they added arcane spells.

In summary, any character can cast spells while wearing armor as long as they are proficient with that armor. However, by default, wizards are not proficient with any armor. To gain proficiency, wizards can gain proficiency through feats, which take three feats to achieve.