The Ed Sheeran-penned ballad is the second to be lifted from their new LP Take Me Home, which has also entered at number one this week, giving the group a UK chart double.
Bruno Mars enters in second place with Locked Out of Heaven, having led the pack in the midweek chart.
Little Mix score their third top three placing with 'DNA', which lands at three. Labrinth drops two places with former number one 'Beneath Your Beautiful' to four.
Gabrielle Aplin climbs a massive 31 places to five with her Frankie Goes to Hollywood cover 'The Power of Love' following its use on this year's John Lewis Christmas advert.
Robbie Williams slips five to six from last week's top spot with 'Candy', while Psy drops one to seven with 'Gangnam Style'.
The Lumineers climb up seven places to a new peak of eight with 'Ho Hey'. Rihanna drops a place to nine with former number one 'Diamonds'.
McFly's new single from their Memory Lane compilation 'Love Is Easy' lands at ten, making it their 18th Top 10 hit.
Ed Sheeran's latest single 'Give Me Love' lands at 18, while Christina Perri re-enters the chart at 19 with 'A Thousand Years' following a new version being used in The Twilight Saga: Breaking Dawn: Part 2.
Stooshe's cover of TLC's 'Waterfalls' is new at 21, while The Wanted's 'You Found You' tumbles 17 places to 20. Misha B also drops 14 spots to 23 with 'Do You Think of Me'.
One Direction climb back up 11 places to 26 with 'Live While We're Young' following the release of their new album Take Me Home.
Lana Del Rey enters at 32 with new single 'Ride', while Pink climbs a further seven places to 33 with 'Try'. Example also sneaks in at 37 with 'Close Enemies'.
Watch the video for One Direction's 'Little Things' below:
Source: Official Charts Company
> This week's albums chart