The singer arrived at Cowdray Park in a star-print dress teamed with a cream coat, black stilettos and her favourite accessory; a Chanel handbag.
Despite the rumours that Allen's vintage store Lucy in Disguise might be closing down, the star was happy to show off her blooming baby bump to the cameras. So she should be; we think she looked lovely!
How do you rate Lily's polo style? Let us know in a comment and take a look at some of her best fashion moments below.