Wikipedia policy requires that every article be based “on reliable, independent, published sources with a reputation for fact-checking and accuracy.” This often leads clients to ask what a reliable source is on Wikipedia, and how we determine if a website qualifies. While it may seem straightforward, the nuances of the sources Wikipedia views as reliable and doesn’t can be idiosyncratic. Wikipedia’s policy is only a starting point. For new or unfamiliar sources, we follow a structured process to determine Wikipedia’s view on their reliability.
Wikipedia’s Reliable Sources Policy
Wikipedia’s reliable sources policy requires that all material be supported by independent, published sources with editorial oversight, and that the type of source match the type of claim. Major newspapers, academic publishers, and peer-reviewed journals form the backbone of reliable sourcing on Wikipedia.
Meanwhile, primary sources may verify simple, non-interpretive facts but cannot be used for analysis or controversy. Self-published or user-generated content is generally excluded except for uncontroversial statements about the author. Reliability depends on context: medical, scientific, and contentious claims require higher-quality sources; tabloids and dubious outlets are rejected for anything beyond trivialities. Sources must be publicly available, even if behind paywalls, expensive, or in institutional archives
This framework is tightly linked to verifiability and Wikipedia’s prohibition on original research or content. Editors may not synthesize sources or draw conclusions from raw data not reported on by reliable sources.
Wikipedia summarizes the policy by stating, “Each book, article, or other source needs to be credible for supporting the particular claim(s) it supports. In case of a dispute, editors need to be able to explain why they relied on that source.” And that every article must be based “on reliable, independent, published sources with a reputation for fact-checking and accuracy.”
While it seems straightforward, there is a labyrinth of rules and practices shaping the usage of sources on Wikipedia. That’s why when we evaluate sources to be used as part of a Wikipedia page creation or editing service, we go through a number of steps to evaluate each source.
The Reliable Sources Noticeboard
When editors disagree on the reliability of a source, their first stop is the reliable sources noticeboard (RSN). The noticeboard is a central forum for resolving disputes over source quality.
At times, discussions center around the general reliability of an outlet (often as a “request for comment”) and, in other cases, sources in articles are evaluated through a case-by-case adjudication system where editors present specific outlets, claims, or contexts for review. Participants evaluate editorial oversight, independence, reputation, and past consensus, often citing earlier RSN threads and real-world standards of journalistic or scholarly reliability.
Technically, the result of RSN discussions are not Wikipedia “policy” but the outcomes create practical precedent. They are frequently cited in deletion debates and content disputes.
The Perennial Sources List
Wikipedia’s community-maintained “perennial sources” (RSP) list is a reference distilling sources that have frequently been discussed on the reliable sources noticeboard into a quick-lookup table outlining how specific outlets are treated on Wikipedia. It lists sources, allowing editors to bypass repeated debates by applying established precedent and providing a handy reference, categorizing them into four main groups:
- Generally reliable: Widely accepted sources with consistent editorial oversight, suitable for most factual claims. (Example: The New York Times)
- Generally unreliable: Sources lacking sufficient editorial control or accuracy, usable only for trivial or non-contentious facts if at all. (Example: The National Review)
- Deprecated: Sources judged so poor that they should almost never be used, and never for contentious or notability-related claims. (Example: The Daily Mail)
- Marginal/unclear, no consensus, or additional considerations: A source whose reliability varies by context or lacks clear community agreement, requiring case-by-case scrutiny. (Example: Business Insider)
The RSP list doesn’t replace policy, but it encodes community judgment, turning years of RSN discussions into a practical, enforceable sourcing baseline.
Notability on Wikipedia for subjects that are not inherently notable is generally determined by the level and breadth of coverage in reliable sources. Sources (like The Daily Mail) that are deprecated are effectively unusable for verification or notability. Sources listed as generally reliable can be assumed to be usable in all but the most narrow edge cases.
Obviously Reliable Sources
Some sources are considered so obviously reliable that their reliability has never been seriously questioned and are missing from the perennial sources list. This doesn’t mean that they cannot be used. It means that their reliability is so well established that they have rarely triggered disagreement (remember, the perennial sources list is intended for sources that are discussed frequently).
This often applies to major non-English international publications. Publications that fall into this category include global newspapers with ironclad reputations such as Le Monde in France, El País in Spain, or The Chosun Ilbo in South Korea. It can also include major cultural magazines, academic publishers, peer-reviewed journals, and other sources with strong reputations.
Their institutional prestige makes them presumptively acceptable under Wikipedia standards, without explicit perennial-list codification.
Checking Existing Usage
If a source is not listed in the perennial sources list and there aren’t prior discussions on the noticeboard about it, you might be left wondering whether that is because the source is clearly reliable or viewed as not reliable. In these cases, one approach we find useful is to search Wikipedia’s article namespace for existing citations to that source. Then evaluate how often and in what context the source appears. Frequent use in well-maintained articles suggests editorial acceptance as opposed to sparse use in marginal pages and recent creations.
You can use the form below to search where a source is used as a source is used on Wikipedia.
This method can help reveal actual editorial practice and implicit consensus when formal guidance is absent on the list and noticeboard.
Local News, Trade Press, and Non-English Sources
Local news and trade press are generally used as valid sources for purposes of verification. Most of these do not appear in the perennial sources list, however, discussions may exist on the noticeboard. Unless special considerations exist, established local newspapers and trade publications are accepted as reliable.
However, when evaluating sources for notability, local news can be discounted when covering their communities, as can trade press for their industries as limited-interest publications. Note that the line between “local news,” which may be disregarded for notability, and regional news, which is usable, can be blurry. This is applied with varying strictness in deletion discussions, but is an important factor to consider when reviewing sources as part of assessing notability.
International and foreign-language sources are an excellent source of information for Wikipedia. Wikipedia is actively working to combat its systematic bias towards the Anglo world and specifies that while English sources are preferred “when they are available and of equal quality and relevance”, non-English sources are acceptable.
Indian and Nigerian news are exceptions due to the prevalence of pay-to-play or “envelope” journalism in those countries. Sources from India and Nigeria, therefore, do not get the same deference as other international publications. Similarly, state-sponsored “fake news” such as Russian disinformation networks are excluded from usage as sources on Wikipedia.
Step-by-step: How to evaluate a source for Wikipedia
Putting it all together, use these steps to align with Wikipedia’s sourcing standards and avoid relying on questionable or inadmissible material:
- Check the Perennial Sources List
Check the RSP list for existing community consensus on the source’s reliability. - Search the Reliable Sources Noticeboard (RSN)
If the source isn’t on the list, check the noticeboard for past community discussions or context-specific evaluations. - Ask: Is It Obviously Reliable?
Consider whether the source is a well-known, reputable outlet (e.g., major international newspapers, academic publishers) that hasn’t needed RSN discussion due to its clear credibility. Conversely, is it obviously unreliable? - Review Existing Usage on Wikipedia
Search Wikipedia articles to see where and how the source is cited using our form above. Frequent use in stable, high-quality articles suggests de facto acceptance and can confirm your assessment of obvious reliability.
Bottom Line
Determining whether a website is a usable source on Wikipedia isn’t as cut and dry as you might expect. It requires navigating community norms, precedents, and editorial practices. While Wikipedia’s reliable sources policy sets a foundation, actual reliability is context-specific and often clarified through the reliable sources noticeboard, the perennial sources list, and by checking how a source is already used across Wikipedia. These are important steps to consider when evaluating sources in preparation for editing or creating articles on Wikipedia.
Considering a Wikipedia article? We suggest starting with a notability assessment to determine if your subject qualifies for inclusion. Buy one here.