Hello, Dolly! is set in New York City in 1890. It starts Dolly Levi whose main job involves matchmaking people. Though she’s looking a wife for him, Dolly falls for Horace Vandergelder. Meanwhile, Horace plans to propose a hat shop owner named Irene Molloy who resides in New York City. Dolly arrives in Horace’s home in Yonkers and tells him to go on his way to New York.
Horace’s two employees, Cornelius and Barnaby, want to get out of Yonkers and Dolly advises them to go to New York City where they should meet up with Irene Molloy and her assistant, Minnie Fay. She also makes Ambrose, a young artist, joins a competition with Ermengarde, Horace’s niece whom Ambrose wants to marry.
At Irene’s shop, Cornelius and Barnaby arrive, pretending that they are rich men. When Horace comes in with Dolly, the two men hide. Minnie is horrified to see Cornelius hiding in one of the armoires but Dolly comes in to check and tells Horace that there’s nothing inside. Afterwards, Dolly arranges a date for Cornelius, Barnaby, Irene and Molly. As the two pairs go on with their date, Dolly seeks her first husband’s permission to remarry. She then meets Horace and tells him that an heiress named Ernestina Semple is a perfect match for him. She also informs him that he can meet the heiress in Harmonia Gardens.
When Horace reaches his destination, he is disappointed that he’s not meeting an heiress but Dolly’s friend, Gussie. Gussie becomes bored during their date and she leaves Horace alone.
When Cornelius, Barnaby, Irene, and Molly arrives at the same restaurant, the two men confess that they are not rich. Irene, who knows all about this, offers to take care of their bill but she realizes that she has left her bag and money at home. At that same moment, Dolly sits with Horace and tells that it’s not just possible for her to marry him. Cornelius and Barnaby and their dates try to sneak out but Horace sees them. He also sees Ambrose and Ermengarde who are coincidentally in the restaurant. Horace fires his employees and Horace tells Dolly that he will not marry her at all cost. Dolly is enraged by this and Horace is left alone again.
Back in Yonkers, Horace makes amends with Cornelius and Barnaby and they start running his business together. The movie ends with Horace realizing that he really loves Dolly and the two end up together at last.