When Facebook and Instagram — along with several other Facebook-owned services — suffered the most severe outage in the company’s history on October 4th, it caused widespread disruption.

As Facebook is the single largest source of referral traffic from social media platforms for publishers, this disruption can be especially challenging.

Data from the Social Media Index, a free tool that tracks and visualizes the proportion of traffic received by online publishers from social media, shows that Monday’s 6 hour outage caused a 40% reduction in daily traffic from Facebook compared with the previous day, and the lowest level since December 2018. Thankfully, the data also shows that once the problem was fixed, traffic immediately returned to normal levels, with Tuesday 5th’s value of 11.94% roughly in line with other Tuesdays.

A similar pattern was also observable when we looked at the numbers for Instagram, although the platform drives significantly less traffic

From Sunday October 3rd to Monday 4th, referral traffic from Instagram fell by 43% to 0.12% before again returning to normal levels the next day. For context, Instagram’s share of referral traffic on the 4th was its lowest in over 3 years, with 0.11% being recorded on January 1st 2018.

Perhaps unsurprisingly, the major beneficiary from Facebook’s troubles was Twitter.

Looking at the data, traffic from Twitter increased by 19% from the day before, with its 1.24% the highest it’s been since the end of 2020.

The importance of Facebook in driving referral traffic for publishers is only underlined by the consequences of outages displayed in the Social Media Index data. Thankfully, these outages don’t seem to have any noticeable effect on user habits, with traffic returning to normal levels the very next day.