seal the deal

American  

[seel thuh deel] / ˈsil ðə ˈdil /

Also close the deal

idiom

1. to complete or successfully negotiate an agreement.

   If our top executive can't seal the deal, no one can.

2. to secure or ensure a successful conclusion: A last-minute goal sealed the deal for Baltimore.

   He had aced both interviews, and if the director liked him that would seal the deal.

   A last-minute goal sealed the deal for Baltimore.

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Etymology

Origin of seal the deal

First recorded in 1950–55

Example Sentences

Inter didn't roll over, with Federico Dimarco and substitute Pio Esposito both going close with angled drives, but Gyokeres struck on the break to seal the deal and allow fans to look ahead to United.

From Barron's

She added in the lyrics that she didn’t feel she could ever have afforded the property without the help of her spouse, admitting that the financial situation made her feel “a bit awkward,” particularly because she says Harbour was the one “pushing” to seal the deal.

From MarketWatch

They showed off T-shirts saying "Seal the deal" during an ovation for the Israeli leader and were arrested for an unlawful demonstration.

From BBC

That the film contains one of the year’s finest performances may seal the deal for more serious viewers.

From Los Angeles Times

She and husband Chris were the first people to view the property in July after travelling 130 miles from their home in Tamworth, Staffordshire, to seal the deal within 48 hours.

From BBC