Three domains control most of what shows up in this SERP feature, and backlinks to individual threads have no measurable effect on inclusion.
Table of contents
Key takeaways
- In Ahrefs’ 145-million-result US dataset, the Discussions and Forums feature was present in 16.93 million SERPs. Worldwide, Reddit appeared in 83.9% of instances where the feature showed up.
- Just three sites account for 76.75% of all links the feature surfaces.
- Facebook overtook Quora in January 2026 for total feature appearances.
- 98.7% of queries triggering the feature carry informational intent, and appearance scales with query length.
- No correlation was found between backlinks to a specific thread URL and how often that URL appeared.
What this is about
An analysis of how the Discussions and Forums SERP feature is distributed across domains was published on August 27, 2026 by Glen Allsopp, Head of Marketing Strategy & Research at Ahrefs. Ahrefs data scientist Xibeijia Guan built the underlying numbers from a corpus of 145 million US Google search results. Sites that publish community content — forums, Q&A platforms, social groups — are directly affected.
The facts
Scale of the dataset
Ahrefs found the Discussions and Forums feature present in 16.93 million results, or 11.7% of the 145-million-result US corpus. Allsopp notes data collection for August was still running at publication time; figures from early August put Reddit’s share at 86.1%.
Reddit’s dominance
Worldwide, Reddit showed up in 83.9% of Discussions and Forums instances. Where it appeared, it averaged 1.29 links per SERP. In the US dataset specifically, Reddit appeared in 87.8% of SERPs where the feature was present. Across 34 countries, Reddit ranked first among all domains in the feature. India was an exception, where Quora outranked it. South Africa was another, where Facebook came first.
Among the top 100 subreddits in the dataset, the average community age worked out to 16 years and one month. r/ScienceBasedParenting, created 8 years ago, was the newest community in that group. No new or low-activity community broke into the top 100.
The three-domain concentration
Just three sites account for 76.75% of all feature links — a concentration the top-25 table below makes concrete. 84.87% of all links go to the top 10 domains; the top 100 account for 91.51%. Once you get to domains ranked 501–1,000, their combined share drops to 1.49%.
Facebook’s trajectory
Allsopp reports that Facebook’s presence rate of 38.3% of Discussions and Forums instances held consistently across countries. All appearances came from public Facebook Groups, not Pages or profiles. Facebook topped the domain rankings in South Africa, Zimbabwe, Zambia, and Samoa, and came second in 23 further countries — among them the US, UK, Canada, and Australia. The crossover point where Facebook’s total feature appearances surpassed Quora’s came in January 2026.
Quora and intent
Quora appeared in 8.22 million search results. Of Quora’s four highest-prominence threads in the dataset, three centered on finding places to stream or watch movies online. Allsopp observed that Quora’s AI Assistant, which he estimates launched around early 2023, supplies top answers in a number of those threads.
Query characteristics
98.7% of queries where the feature appears carry informational intent. 40.9% also carry commercial intent (Allsopp notes keywords can hold multiple intent classifications). Navigational intent accounts for 0.6%. The feature appeared for 0.3% of single-word queries. Compared with the average across all query lengths, an eight-word query triggers the feature at roughly triple the rate. 43.2% of appearances involve queries of five or more words.
Domain age
Registration dates were retrievable for 984 of the top 1,000 domains. Those 984 domains averaged 21 years and 8 months since registration. The Gear Forum, a guitar community ranking 748th worldwide and present in 1,200 separate results, was the newest domain in the top 1,000 without a redirect history — its registration sitting at just under four years back.
Single-URL concentration
For 27 domains inside the top 1,000, a single URL accounts for 10% or more of that domain’s total appearances in the feature. A Gleneagles Hospital health-question page accounted for 67% of that domain’s appearances. A 2020 post on skill.jobs — with no replies — drove 30% of that site’s presence in the feature.
Backlinks
Domain Rating averaged 58.3 across the top 1,000 domains. There’s a moderate Spearman correlation (ρ = 0.38) between DR and prominence, but Allsopp attributes this almost entirely to the top of the list. At the URL level, URL Rating and appearance frequency showed no correlation across the top 1,000 individual discussion URLs. Only 6 of the top 100 URLs had any UR score at all, and none exceeded 5.
What we can and cannot say yet
What the data shows: Concentration in this feature is extreme and has been stable long enough that Allsopp describes monitoring it “for years.” The Facebook-overtaking-Quora shift in January 2026 is a documented change in relative standing, not a projection.
What remains open: The analysis covers a US-anchored dataset with global country breakdowns. Whether the same concentration ratios hold across different markets is not fully answered here. Allsopp flags that domain registration dates don’t capture when a forum actually launched or whether a domain was redirected, so age figures should be read as proxies.
The backlink finding is the most practically significant null result in the dataset, and it belongs with the other tactics that thin out under testing. A ρ = 0.38 at the domain level, driven by the top of the list, is not evidence that building links to forum threads improves feature inclusion. Allsopp states explicitly that no such correlation was found at the URL level.
What to watch
The early August figure — Reddit appearing in 86.1% of results — sits higher than the 83.9% full-dataset average. If that holds through the complete August count, it’s a measurable uptick worth tracking month-over-month. In Ahrefs’ Site Explorer, pull up any domain, open the Organic keywords report, and filter for “Discussions and forums” with “Include target in” selected to see where that domain is already showing up in the feature. Presence in the feature is worth what it converts, and that gap between visibility and value is the harder half to measure. The number most worth watching isn’t Reddit’s share. It’s whether Facebook’s January 2026 lead over Quora keeps widening or whether Quora finds a floor. That gap is what’s most likely to move in the next two quarters.
| Domain | SERP appearances | Links per SERP | % of Discussion SERPs |
|---|---|---|---|
| reddit.com | 21.77M | 1.31 | 84.71% |
| facebook.com | 9.84M | 1.36 | 38.29% |
| quora.com | 8.22M | 1.33 | 31.96% |
| justanswer.com | 2.1M | 1.28 | 8.16% |
| mayoclinic.org | 839.4K | not reported | 3.26% |
| stackexchange.com | 423.9K | 1.07 | 1.64% |
| tripadvisor.com | 290.3K | 1.15 | 1.13% |
| practo.com | 280.2K | 1.27 | 1.09% |
| steamcommunity.com | 280.1K | 1.35 | not reported |
| stackoverflow.com | 188.8K | 1.19 | 0.73% |
Source: Glen Allsopp and Xibeijia Guan, Ahrefs, August 27, 2026. SERP-appearance totals in this table reflect worldwide data; the 145M-result US corpus is the basis for US-specific figures such as the 16.93M feature-present SERPs. The full top-25 table appears in the source report.
