@JeremyECrawford Does casting a bonus action spell still allow you to cast a normal spell then still get a reaction spell?
— Jason Eau Clair (@Nasagi) September 27, 2015
Casting a bonus action spell means no other spells that turn but a cantrip with a casting time of 1 action. #DnD https://t.co/SGcrax6SrT
— Jeremy Crawford (@JeremyECrawford) October 9, 2015
Sorry to debate this, but: why does sage the advise article http://dnd.wizards.com/articles/sage-advice/ability-check … state that a reaction can be done too?Each paragraph of the answer addresses the question—can you cast more than 1 spell on your turn?—and nothing in the 3rd para. undoes the 2nd
— Jeremy Crawford (@JeremyECrawford) June 1, 2017
It is of note that turn is not equivalent to round.
What about doing a regular spell first and than another spell as a bonus action?
Casting a “regular” (level 1+) spell means that you can’t cast a BA spell on your turn (and BA, RAW, only occur during your turn for you — they can’t be “held” or used via a Reaction). You could still cast a Reaction spell (as they require less metaphysical “twisting/oomph” than a BA spell does) and if you have Action Surge (or similar by whatever means) you could cast a “regular” spell with that… but still no BA spells. In short: BA spell = no other spells your turn except cantrips; cast a “regular” spell (or a Reaction, or Action Surge non-cantrip), then no BA that turn/round.