Continuity mistake: The shape of the staircase in the living room is slightly different to the original one. In Full House, the lower half of the stairs before the midway landing was shorter (roughly 5 steps) and the upper half was longer (about 7 steps) where as in Fuller House, the lower half is now the longer section (about 7 or 8 steps) and the upper section after the midway landing is shorter (roughly 5 steps).
Continuity mistake: When Full House started, it was stated that D. J was 10, Stephanie was 5 and Michelle was a baby. The Tanner girls were five years apart but in Fuller House, Stephanie says, "I'm 36", in response to an old lady calling her older than 50. But, D. J's 40th Birthday is not until the next season. D. J was still 39 at the time so Stephanie couldn't have been 36 or else D.J. would have been 41. Also, DJ's 39th birthday is in S2 and her 40th is in s5?
Continuity mistake: In the original Full house, there was a closet in the room that ended up being DJ's but that closet seems to have disappeared in the Fuller house episodes when they show what is now Tommy's room.
Our Very First Show, Again - S1-E1
Audio problem: After Stephanie takes back the flash drives she gives to Max and Jackson, Max tells D.J. that he knows all the bad words. When we hear him say "Donald Trump," his lips do not match it. (00:06:40)
Our Very First Show, Again - S1-E1
Continuity mistake: When D.J. is talking about finding a place to live, she is holding a few things. The way she is holding them changes between shots. (00:07:25)
Our Very First Show, Again - S1-E1
Continuity mistake: When DJ is talking to Steve in the kitchen, the calendar in the background for chores changes between shots. (00:23:00)
Our Very First Show, Again - S1-E1
Continuity mistake: After Jessie has Tommy dance on the counter there are placemats on the counter that keep changing position each shot for the entire scene.
Our Very First Show, Again - S1-E1
Continuity mistake: At the beginning of the episode when everyone is sitting at the table, Tommy's bottle is on his highchair in some shots and on the table in others.
Our Very First Show, Again - S1-E1
Continuity mistake: In Full House Niki and Alex's room is big enough to fit multiple children's beds. When Ramona is given the room here it is barely big enough to fit a bed.
Our Very First Show, Again - S1-E1
Continuity mistake: When Jessie is done singing "Forever" Stephanie is holding a tambourine. Everyone starts clapping, and Stephanie is not holding anything in her hands. The shot changes and she is holding the tambourine again.
Moving Day - S1-E2
Continuity mistake: In the original Full House, the attic that Becky and Jesse lived in is completely different from the one in this series. When D.J. shows Ramona her room where Nicky and Alex stayed, it's on the opposite side of the attic and is much smaller than the one in the original. (00:07:00)
Moving Day - S1-E2
Continuity mistake: After Stephanie says "gone horribly wrong." She crosses her arms, the shot changes and her hands are now on her hips. (00:22:30)
Moving Day - S1-E2
Continuity mistake: In Full House, Nicky and Alex's room is spacious but when D.J. shows Ramona the room here, it is tiny and they can hardly fit into it. And it is on the other side of the bedroom.
Moving Day - S1-E2
Continuity mistake: When Stephanie is holding Tommy and talking to D.J. on the phone, in one shot Tommy is holding a toy that he was not holding earlier or after.
Moving Day - S1-E2
Continuity mistake: In the opening scene in the kitchen the straw in the milk shake switches between standing straight up and leaning against the glass between shots.
The Not-So-Great Escape - S1-E4
Continuity mistake: Jackson is holding a paper. D.J. says "I think we can agree both of you being punished is fair." The shot changes and he is no longer holding the paper. (00:21:40)
The Not-So-Great Escape - S1-E4
Continuity mistake: Jackson rips the paper he is holding and gives half to Ramona, later on in the scene the paper is ripped differently. It then changes back to the original way.
The Not-So-Great Escape - S1-E4
Continuity mistake: When Max is choosing what puppy he wants, Tommy's stroller can be seen in the background. The shot changes and the stroller has moved.
Revealing mistake: When Shannon walks into the kitchen and gives Stephanie a hug, in one shot of the highchair where Tommy is sitting there is now a doll.
Continuity mistake: When Max and Jackson are in their room when Max finds out Stephanie left, his trombone keeps changing position between shots.
