After looking over these lists, I realized that I am not a fan of the rom com. The only movie on these lists that I enjoyed was The Sound of Music, which might be rom but isn’t, IMHO, com.
Love Actually
High Fidelity
And since we are including musicals from other eras–Gigi
You’ve Got Mail, hands down.
Bridget Jones Diary
The Truth About Cats and Dogs
While You Were Sleeping
Kate and Leopold
Joe Versus the Volcano
The relatively little-known (including by me, until my daughter told me about it) “Obvious Child,” 2014, with Jenny Slate.
The granddaddy of them all: It Happened One Night
I can never decide between my favorites - several great ones have been mentioned, but I’d have to add
Legally Blonde and Legally Blonde 2
as well as
Dave
to the list
Favorite rom: Somewhere in Time. I hope for a different ending every time I watch it. Rom com: Notting Hill because I watched it at least 3 times on a flight to London and then made a point of looking for the Travel Book Shop in Notting Hill (fun memories).
In no particular order:
Philadelphia Story
The Lady Eve
The More the Merrier (Joel McCrea and Jean Arthur)
Woman of the Year (Tracy and Hepburn)
It Happened One Night (Colbert and Gable)
Say Anything
The Cutting Edge (secret shame 
)
Does Sullivan’s Travels count?
Honorable Mentions :
Sabrina (Hepburn and Bogart)
Palm Beach Story
The Clock (Judy Garland and Robert Walker, although it isn’t a com, just a rom, I have to mention it)
Love Actually
Four Weddings and a Funeral
While You Were Sleeping
Bringing Up Baby
My Favorite Wife
The Lady Takes a Chance
Various comedies starring Jean Arthur and Irene Dunne and Gary Cooper and Joel McCrae
You guys are giving me some great suggestions to watch this winter! I think the new Reese Witherspoon movie that just came out this week looks good.
I love so many that you have listed.
I would say Dirty Dancing, but is that really a rom-com?..I guess so.
I will say my favorite true rom-com is probably Working Girl. (Melanie Griffith and Harrison Ford)
Love Dirty Dancing, but it is definitely a rom, not a rom-com.
Working Girl! I love that one. Thanks for the reminder.
You know what’s a good Rom-com? Much Ado About Nothing. The recent Josh Whedon version is particularly charming especially if you are a Firefly fan since half its cast is in it.
@mathmom, a friend told me about Much Ado About Nothing just recently. Its one of her favorites. Putting it on my rainy day movie list.
It is a kids’ movie… but it is a romantic comedy of sorts - we love it!
Enchanted with Amy Adams.
Stardust is a fun one! Family friendly like Enchanted but with a Princess Bride slant.
if you’re including oldies, what about an affair to remember
Have to agree on Before Sunrise–not a rom-con but wonderful romantic story.
Dan in Real Life (friend’s family used to own the vacation house used in the movie) and
Love Actually.
Another fan of Before Sunrise, and the rest of the trilogy, Before Sunset and Before Midnight, although the latter two are less romantic given the subject matter but realistic. Worth watching if you haven’t seen them.
We recently watched them all (Sunrise, Sunset, Midnight), after so many recommendations from JHS. To my surprise, I think DH liked them even more than I did. It was fun watching Ethan Hawke and Julie Delpey get older in real time. (They were filmed over a 12 year span.)