Market research firm NPD has now recorded a full month of console sales for the PS4 and Xbox One in the US, and it's revealing today that Microsoft’s latest console topped the sales charts for the month of December. Microsoft has long dominated with the Xbox 360 in the US, and it appears that healthy stocks of the Xbox One have helped the company take the edge during the all important holiday season. Microsoft’s Xbox One sold 908,000 units in December, alongside 643,000 sales of the Xbox 360. Both of Microsoft's consoles topped the charts in the US for each generation.

Sony blames stock issues for PS4 US sales

The NPD figures follow announcements earlier this month from Microsoft and Sony over their console sales for 2013. Microsoft revealed it sold more than 3 million Xbox One consoles in 2013, while Sony sold 4.2 million PS4s last year. Sony is currently selling its PS4 console in 52 countries, while Microsoft has not yet expanded its initial 13 launch markets. Sony is blaming stock issues for its PS4 US sales in December. "We sold every PS4 available at retail in the US and were out of stock in December due to overwhelming consumer demand," says Sony's Dan Race. "PlayStation 4 remains the cumulative leader for next-gen console sales in the US since the launch on November 15th."

Sony's "cumulative leader" claim could be largely related to the extra week of sales in the US during November, adding to the overall combined total for November and December. Sony launched the PS4 on November 15th in the US, followed a week later by Microsoft's Xbox One. Either way, both consoles are clearly off to a great start, and both will be boosted by more and more titles launching during the course of 2014.

Update: article updated to reflect comments from Sony on its US PlayStation 4 sales.