"15 beautiful years," she captioned the first pic of her embracing her husband as, to quote the Spice Girls, two became one. "We feel so blessed and thankful for your love and support over the years. Such a special day x."
The couple tied the knot at Luttrellstown Castle in Ireland in 1999, and Victoria wore an ivory gown with a $17,000 diamond coronet on her head.
Their 4-month-old son Brooklyn was ring bearer at the ceremony, and the former Posh Spice shared a pic of the family, writing: "How cute is Brooklyn! Such a special day with David today x"
The mother of four also posted a photo taken at the reception, where the newlyweds changed into matching purple outfits.
"Thank you for your beautiful messages," Victoria, 40, wrote to fans and well-wishers. "Its such a special day for us both. Your love and support means so much."
15 beautiful years.We feel so blessed and thankful for your love and support over the years.Such a special day x pic.twitter.com/rHZJdDoj9Y— Victoria Beckham (@victoriabeckham) July 4, 2014
Thank you for your beautiful messages.Its such a special day for us both.Your love and support means so much x vb pic.twitter.com/A8S0PkMgIt— Victoria Beckham (@victoriabeckham) July 4, 2014