The newlywed shared a snapshot from her honeymoon with her Instagram followers this week, showing her sunbathing in a swimsuit and holding a cocktail.
She also made a point of publicly using her new name, captioning the picture, "Jessica Johnson".
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Jessica Simpson shared this honeymoon photo on Monday - and signed off Jessica Johnson
It's the second picture that mum-of-two Jessica has shared from her post-wedding holiday with husband Eric Johnson.
She celebrated her 34th birthday on 10 July by posting a selfie which was captioned, "And the sun sets on 33."
Jessica and Eric, 34, chose the luxurious Four Season Punta Mita Resort in Mexico, to unwind following their fourth July wedding weekend, US Weekly reports.
Jessica Simpson: 'And the sun sets on 33'
"They had an amazing time and looked so in love during the entire visit," a fellow guest said of the couple, who stayed in one of the hotel's presidential suites.
"They enjoyed cocktails by the pool and spent a lot of time on the beach, just relaxing after their big day."
Jessica and Eric tied the knot at the San Ysidro Ranch following a three year engagement – and the arrivals of daughter Maxwell, two, and son Ace, one.
Jessica Simpson and Eric Johnson with their children, Maxwell and Ace
The bride wore a custom Carolina Herrera champagne gown with gold embroidery.
"Everyone thought I was going to wear a dress that completely showed off my new bod," the Weight Watchers spokesperson told People. "But I can't help but want a princess dress. I'm a southern girl at heart. I like everything big!"
Her husband thought she looked perfect. "She was all lit up and beautiful," he told the magazine of Jessica's walk down the aisle. "I think my heart was exploding a bit."