I'm not picky about a lot of things other agents are.
But you can shoot yourself in the foot with ineffective salutations.
Here, in descending order of preference, are effective salutations in a query letter.
1. Dear Janet
It's my name, I'm ok with you calling me Janet.
Dear Jessica isn't right but it's probably just a typo, and I'll get over it. Besides I love snaring good stuff right out from under the nose of Jessica Faust.
2. Dear Ms Reid
Also my name, a tad more formal, but still very polite.
3. Hi Janet, Hi Ms Reid
More informal, but if you just can't bring yourself to say "Dear" (and I've had husbands who couldn't either) it's ok to just say hi.
The next ones make me roll my eyes, but we haven’t gotten into active yeesh mode yet
4. Dear Jet Reid Literary Agency
It is just I here at Shark Central these days. I read all my own queries (always have).
It's not a deal breaker but it seems like you're not paying attention.
I feel like I'm being drafted or summoned for jury duty. It's not wrong, but the tone is a little too military to be effective.
And now we get to the ones that really set the WRONG tone and you should avoid.
6. To Whom It May Concern.
This is a salutation you would use ONLY with letters where you do not know who the actual recipient is. For example: a reference letter you provide to someone who is job hunting, or seeking parole.
Since you're emailing your query to Janet@(yadda yadda) this situation doesn't apply.
Now, you nit pickers may ask, what if I'm querying Queries@Villains.com?
THEN you use the very handy form of Ladies/Gentlemen of Villains.com as your salutation.
In the olden days, back when ladies in business were a well-kept secret, it was considered acceptable form to start with Gentlemen:
That is no longer acceptable. I am not a gentleman. And most of the gents I know are rapscallion scallywags anyway.
7. Dear Mrs Reid.
I am not married to Mr. Reid.
My father is not Mr. Reid either.
So, it's just plain wrong to call me Mrs. Reid.
But further, it signals a mindset that you would even use Mrs. at all, and that mindset is NOT what I'm looking for in clients.
If a lady prefers Mrs. she'll say so.
And while we're on the subject of what people like to be called, make sure you pay attention if someone has preferred pronouns in their bio or signature line. USE THEM.
Any sort of ham-fisted, tone-deaf, rigidity here is NOT good manners, or smart querying.
If someone wants to use the title Mx., do so.
And don't belly ache to me that it's too much trouble. It's not like I'm not doing this myself when I query editors I don't yet know. Or reaching out to anyone I don't know (think blurbs, reviews, sales pitches to bookstores.)
It's a new word my fiends, time to get with the times.
8. Dear Mr. Reid
As above, I am not a man. I may cook like one and sew like one, but I'm still not one.
9. Dear Felix,
When you send Dear Felix to Janet@GettingSnarlyAboutThis.com I draw some unflattering conclusions about how much attention you pay to detail.
Think about this for a minute. I have a choice between someone who double checks things like salutations, and someone who doesn't. Who do you think I prefer to work with?
10. No salutation at all.
Nope nope nope.
And if you want to howl about this, fine.
It's not going to change.
I don't ask you personalize in any other way, but I do like to see that you know at least who you're querying.
I don't care about why you're querying. I'm an agent, you're a writer, enough said.