Kate Middleton is back to brown after appearing with her blondest hair ever last week.

On Sept. 8, the Princess of Wales, 43, made a surprise appearance by joining Prince William at The National Federation of Women’s Institute in Sunningdale to commemorate the third anniversary of Queen Elizabeth’s death.

Princess Kate wore her long hair down in loose curls, and her hair was a brunette hue with highlights.

Kate’s latest engagement confirmed her recent hair color change, following a stint with a brighter honey blonde from late August into September.

The Princess of Wales was initially spotted with lighter locks for a church outing near Balmoral Castle on Aug. 24.

Princess Kate’s hair change was on full display the following week when she stepped out at London’s Natural History Museum on Sept. 4, where she appeared with honey blonde locks.

The shakeup shocked royal watchers as the new hue marked Kate’s boldest hair transformation to date, and the length also appeared to be the longest ever. The Princess of Wales has rarely deviated from her signature brunette tresses, often styled in a bouncy blowout, since marrying into the royal family in 2011.

However, the light look didn’t last long. On Saturday, Sept. 6, her hair was a darker brown again when she stepped out to attend the Women’s Rugby World Cup match between England and Australia in East Sussex.

There, Princess Kate wore her long locks pulled back in a half-updo with curls. It looked like her hair was darker, but the slicked style made it difficult to discern for sure.

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Over the summer, the Princess of Wales’ hair had been a rich chestnut when she attended event including Trooping the Colour in June and the French state banquet in July.

Her hair was a glossy chestnut color when she went to the Wimbledon Championships on July 12 and 13, her last public appearances before retreating for summer break.