Taking to her Instagram Stories, the Lizzie McGuire star posted a selfie of herself at a vaccination centre getting the jab.
The actress wore a grey sleeveless top and pink mask, and captioned the post with: "I got vaccinated."
WATCH: Hilary Duff announces her third pregnancy in sweet video
A second post showed her driving home after getting the jab, with a plaster on her arm. As she stuck her tongue out, she wrote: "Other people raging, other things today… I got that Pfizer."
After getting her vaccine with her husband, Amanda urged her fans to follow suit. "It's better than OK to get vaccinated because states are rapidly expanding eligibility," she explained.
The star posted a snap of her getting the vaccine
"Schedule, get your name on a list (as we did in Georgia), or contact your local Covid Angels as soon as you can."
Amanda finished her post with an inspiring message, as she wrote: "We're gonna get to the end of this together!"
Hilary's vaccination came just weeks after she gave birth to her third child, Mae.
In an announcement, the star shared an adorable photo of her in the birthing pool, cradling her newborn alongside her other daughter, Banks.
Her husband, singer Matthew Koba, and son, Luca, from her previous relationship with NHL player Mike Comrie were outside the pool. "Mae James Bair- We LOVE you beauty 3-24-21," Hilary lovingly wrote for her new daughter.
The star was in high spirits after the jab
The singer revealed that this pregnancy wasn't plain sailing, and shared a snapshot of herself laying down on her bed.
"When the pregnancy sciatica gets you," the star wrote. Sciatica is where the sciatic nerve, which runs from the lower back down to the feet, is compressed or irritated.
Hilary was also admitted to hospital over the Christmas period with an eye infection. But her claims that it was caused by frequent COVID tests were disputed.
Last year, the singer welcomed a niece, and shared an adorable photo of the tot wrapped up in a blanket.
She wrote: "Look at this gorgeous addition to the family. Welcome baby Fallon!! We love you so much and couldn't wait for your arrival. Congrats @emilymazzarisi and @bigfatsnaredrum @matthewkoma and I are going to spoil her rotten!"
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