How does Readying a spell work?

@JeremyECrawford How does Readying a spell work? Do you lose your spell slot if the trigger effect never occurs? — John F Ezell (@EZotor_23) August 29, 2015 A readied spell's slot is lost if you don't release the spell with your reaction before the start of your next turn. https://t.co/0K59zeZLjX — Jeremy Crawford (@JeremyECrawford) August […]

Ready a spell, should there be a concentration check for all spells?

@luminapinaMage slayer/ready action hits while casting a spell. Should there be a concentration check for all spells, excl. maybe cantrips? readied action takes place after trigger, so first spell then attack. No check needed. — Mike Mearls (@mikemearls) October 8, 2014 @luminapinaOkay, thank you. So Counterspell is the only way to interrupt the casting of […]