The couple have been dating since 2006. They briefly split last year, but reunited quickly after realising they couldn’t bear to be apart.
They have now confirmed they are set to tie the knot, after Nick proposed “near a beach” in California.
“We're excited and incredibly happy about our engagement and we look forward to a wonderful future together,” they said in a joint statement.
According to People, Nick popped the question with an “Asscher-cut diamond with baguettes from Bader & Garrin”.
Nick, 36, can hardly contain his excitement about his impending nuptials. He has already discussed them on Twitter, taking to the social networking site to tell fans how happy he is.
“Hey all. If anyone's heard the rumours of my engagement, they are absolutely true! Vanessa and I couldn't be happier. Thanks for all the love,” he wrote.
Vanessa, 29, has previously spoken of her desire to walk down the aisle. She has also been open about how in love she is with Nick, and thinks nothing of revealing the intimacies of their romance. She recently admitted they usually shower together, although she insisted it is not for sexual reasons.
“It just becomes an intimate thing... I've had some of my most intimate conversations with him in the shower,” she explained.
The union will be Vanessa’s first marriage, although Nick was previously wed to Jessica Simpson.