Opportunity source is the field in a CRM that records where a sales opportunity originated: which channel, campaign, or team action first generated the contact or account that became the opportunity. It is the attribution field at the opportunity level and determines how pipeline and closed revenue is credited to different marketing and sales activities.

Opportunity source data quality directly determines the accuracy of sourced pipeline reporting. If opportunity source fields are often blank, populated inconsistently, or overwritten when new touches occur, the resulting reports misattribute pipeline and lead to poor investment decisions. Source field governance, the rules and enforcement around how and when source fields are populated, is a critical RevOps responsibility.

The most reliable approach is to set opportunity source automatically at the moment of opportunity creation by inheriting the original lead source from the contact record. This removes human error from the attribution process and creates a consistent, unbiased record of where each opportunity came from.

Analytics terms are useful only when they change a decision. A metric can look sophisticated and still be low value if nobody knows how it is calculated, which segment matters, or what action should follow when it moves. It usually becomes more useful when it is defined alongside Lead source, Attribution, and Pipeline.

The practical way to use it is to pair the term with a calculation rule, a reporting owner, and a review cadence. Then segment it by source, audience, and funnel stage before drawing conclusions from a company-wide average. Teams often get better results when they connect Opportunity source to Lead source and Attribution instead of managing it in isolation.