"Mama Do (Uh Oh, Uh Oh)" debuted at number one on the UK Singles Chart, selling 58,840 downloads in its first week. Lott described her reaction upon learning the song reached number one: "I was in bed at my mum and dad's, where I still live, in Brentwood, Essex. I was on the laptop, and I got a phone call from my A&R man. He really dragged it out. I said, 'Please put me out of my misery.' And he said, 'I'm really, really sorry but... you're No 1!' I spent the rest of the day running around the house, screaming."

The single was certified silver by the British Phonographic Industry (BPI) on 28 August 2009 for sales in excess of 200,000 copies. Exactly 11 years later, on 28 August 2020, the certification was upgraded to gold for sales and streams of over 400,000. As a result of the single's popularity at the time, the single's iTunes B-side, "Use Somebody", debuted and peaked, during the single's release week, on the UK Singles Chart at number 52 on sales of 4,409 downloads.

The single also had considerable success outside the UK, reaching the top 10 in Denmark and France, and the top 20 in Ireland, Netherlands and New Zealand.
Was the Pixie Lott song "Mama Do" ever the #1 single?
"Mama Do" debuted at #1 on the UK Singles Chart in its first week and also was successful outside the UK, appearing in the Top 10 in Denmark and France and the Top 20 in Ireland, the Netherlands, and New Zealand. The British Phonographic Industry certified it as Silver the same year it was released and upgraded the certification to Gold eleven years later.