Adina and Belcore's wedding party is in full swing. Dr. Dulcamara encourages Adina to sing a duet with him to entertain the guests. The notary arrives to make the marriage official. Adina is annoyed to see that Nemorino has not appeared, for the whole deal has been intended only to punish him. While everyone goes to witness the signing of the wedding contract, Dulcamara stays behind, helping himself to food and drink. Having seen the notary, Nemorino appears, depressed, as he believes that he has lost Adina. He sees Dulcamara and frantically begs him for a more powerful, faster-acting elixir. Although Dulcamara is proud to boast of his philanthropy, upon discovering that Nemorino now has no money he changes his tune and marches off, refusing to supply him anything. Belcore emerges, musing about why Adina has suddenly put off the wedding and signing of the contract. He spots Nemorino and asks his rival why he is depressed. When Nemorino says he needs cash, Belcore suggests joining the army, as he'll receive funds on the spot. Belcore tries to excite Nemorino with tales of military life, while Nemorino only thinks of getting the potion and thus winning Adina, if only for a day before departure. Belcore produces a contract, which Nemorino signs in return for the money. Nemorino privately vows to rush and buy more potion, while Belcore muses about how sending Nemorino off to war has so easily dispatched his rival.