And of course, Jaunita down at the diner, Barney Fife’s girl (sometimes).
Ugly Naked Guy on “Friends”
Joe Mayo on “Seinfeld” (This character was repeatedly mentioned in a variety of contexts. I don’t think he was ever shown, but I’m pretty sure he was named after someone on the crew of the show.)
Nanny on “Muppet Babies” 
Cheating - I know, since we see her fashionably-striped stockings, just never her face.
I know there are more – just can’t think of 'em.
How about Serge (?), Edwina’s son from Ab Fab.
Joe Mayo was seen at his apartment warming party, remember he had the same fur coat as David Puddy.
Anyway, sticking with Seinfeld. Kramer’s two friends, Bob Sakimano and Lomez were never seen. Actually Lomez was probably in the bar when Kramer was telling his “real Peterman” stories but they never referred to him.
Sakimano!! THAT’S who I was thinking of – thanks for the correction. Joe Mayo was indeed in that episode, and was portrayed by Pat Finn.
Starr Jones’s neck.
Didn’t the skinny corpsman with the beaky face do the announcements? I always thought that was his voice.
Mjollnir
Star Jones has a neck?
Once we start talking about MAS*H there are many characters we learned a lot about but never saw:
Peg & Erin Hunnicutt
Honoria Winchester
Mrs. Blake
Mildred Potter
the elder Mr. Pierce
Mrs. O’Reilly and, err, her brother (wasn’t Radar’s uncle helping Radar’s widowed mother with the farm?)?
And Arken, I’m glad you brought up the P.A. announcer…many people mistakenly think that was Radar, but of course, the voice continued even after Radar left the show.
Any adult on a Peanuts cartoon.
How about Peg’s mother on “Married with Children?” She was unseen because the role was originally written for Divine, who passed away before (s)he was able to film an appearance on the show. Rather than get another actor the writers decided to leave the role unfilled and referred to her without showing her on camera.
Another good one is “Charlie” from “Charlie’s Angels.” While his voice (played by John Forsythe) was depicted as coming out of the phone speaker at the start and end of every episode, he was never seen on the show.
And since we’re including BritComs in this thread, how about “Old Mr. Grace” from “Are You Being Served?” He was referred to on several occasions, usually when somebody was introduced to the doddering Young Mr. Grace:
Mr. Spooner: “THAT’S Young Mr. Grace?!?”
Mrs. Slocombe: “Yes. Old Mr. Grace doesn’t get around very well any more.”
Regards,
Zappo
who spends too damn much time in front of the television
Wasn’t Old Mr. Grace the original Mr. Grace and Young Mr. Grace replaced him later on in the series or am I imagining things?
Oh, and with the listing of all of the family on MAS*H you never saw, you can’t forget Klinger’s extended family (including sneaky Uncle Abdul) and his ex-wife.
Mildred Potter made an appearance as a regular on the unfortunate After-MAS*H.
In a reversal of this sort of thing, the WB network cartoon Freakazoid! actually DID show “faceless” announcer Joe Leahy on several occasions AND called him by name.
Oh, and I just thought of one other character… Jim Dial’s wife on Murphy Brown.
Wow, I watch way too much TV.
There was also Columbo’s wife, if you don’t count the “Mrs Columbo” series with Captain what’s-her-name. And I don’t.
Just thought of a few more:
Ralph and Potzie’s parents on ‘Happy Days’
Antonio’s weird girlfriends (Pencil Patty who lives under the bridge, the big-faced girl, etc.), Lowell’s jock pals and Roy’s drinking buddies on ‘Wings’
Suzanne’s voodoo maid Consuela on ‘Designing Women’
That guy who hosted ‘Remote Control’ on MTV’s mom (she always called him up from the basement at commercial time)
Not exactly a character, but…
Northern Exposure made frequent references to the town of Sleetmute, especially if something seedy was being discussed (e.g. “If you want a prostitute, you can go to Sleetmute!”)
Quite a few British comedies have used this convention. Probably the best known (over here, and in my age group…) would be Captain Mainwaring’s wife Elizabeth in “Dad’s Army”, and Arthur Daley’s wife, “'Er Indoors” in “Minder”.
IIRC, in “Are You Being Served?”, Young Mr. Grace was the original proprietor, Old Mr. Grace put in an appearance in later seasons (I think the actor playing Young Mr. Grace either died or retired at some point). Come to think of it, the show included two other invisible characters, Mr Humphries’ mother and (groan) Mrs. Slocombe’s pussy…
I think. I am not an authority on “Are You Being Served?”, I wish to make that absolutely clear.
I’m sure that she was seen. Anyone else remember her?
I read somewhere that the voice for the P.A. system wasn’t a single person at all. It was whoever was around to do it at the time.
Bad TV time. How about “Voice” on Cleopatara 2525?
No, I know for sure we saw Jim’s wife. (drawing a blank on her name…Doris?)
The reruns of “MB” are on Lifetime and I just saw one with her…she wanted to go out and get a job after years of being a housewife. I’m pretty sure she was in at least a couple of episodes.
I’m quite sure we saw Ralph’s father…he was an eye doctor, (right?) and Fonzie went to see him once. Didn’t he and Ralph go to an opthamologist’s convention once? He was a big practical joker? Wanted Ralph to be an eye doc, too?
Lowell’s friends…I know we saw a couple of them once…he and Antonio went rat-shooting at the dump and we saw two of them…they liked Antonio better than Lowell because he shot better, so Antonio shot poorly the next time.
Suzanne’s maid Consuela…I think we did see her at least once, but I’m not positive.
I watch way too much TV, too.
If we include recurring announcers, and going way back, there was the train announcer on the Jack Benny Show, voiced by Mel Blanc:
Train Announcer: Anaheim, Azusa, and Cuc-a-monga …(Pause Between Cuc and A-monga)
Y’know, this is fun and all, but it’s really better suited for IMHO. Catch, Veb!
Oh, and by the way, Dr. Claw from Inspector Gadget (the animated show, not the live-action movie), and, of course, Cecil Adams, from the short-lived Straight Dope TV show.
Arken:
Not quite enough, apparently. Jim Dial’s wife Doris appeared in many episodes from 1989-92. There was even an episode that focused on the two of them (she was leaving Jim because she felt unfulfilled, in a storyline perhaps deliberately derivative of the episode of Mary Tyler Moore where Lou Grant’s wife left him for similar reasons).
urlnotfound: Pretty sure you’re mainly mistaken re: the PA announcer; the voice was very distinctive, and IMDB only credits two voice actors (who were both uncredited in the show itself): Todd Susman and Sal Viscuso.
Todd Susman was the voice we all think of; he’s the guy who sounded a little like Radar. He’s not just a voice actor, either. He’s one of those character actors who turns up in movies and guest roles on TV shows. His best known (to me) recent work was on Angel, as the wealthy father of a young woman who hired Angel to protect the daughter (but got Wesley instead).