Candidate sources: finding out which one brings people who stay

Echipa HR 365 · reviewed 2026-09-07 · 5 min read

The source that brings the most applications is almost never the one that brings the best hires. Measured on volume alone, recruitment allocates money exactly where the noise is loudest — and the figure that counts, the twelve-month retention rate, only arrives a year later.

The four figures, in order of usefulness

The order in the table is also the reverse order of availability: the most useful figure comes last. Which is why most companies decide on the first two — the only ones they have — and why the decisions systematically favour volume sources.

Attribution: where the data breaks

A candidate sees the advert on a platform, asks an acquaintance who works with you, then applies through the careers page. Which is the source? All three — and that is why last-touch attribution, the default in most systems, systematically overvalues your own page.

The rule that produces usable data

1. Recruitment — ask directly, at first contact: “how did you hear about the role?” — do not infer from the channel
2. Recruitment — if the answer includes a referral, that is the source; a referral always beats a channel
3. Recruitment — record one answer, chosen by the rule above, not a list
4. HR — review the source list once a year; one used three times does not deserve to stay a category

The second rule changes the picture most. Referrals are, in most companies, the best source by retention rate and the most undervalued in reports, precisely because people apply through the usual channel.

Cost per hire, by source

The last exclusion matters and is often forgotten: referrals are the best source and the most limited. A company of fifty cannot hire twenty a year through referrals alone, however well it works.

What you do with what you learn

• Move budget from high-volume, low-retention sources to low-volume, high-retention ones — up to their saturation point.
• Invest in the sources that cost attention rather than money: the careers page, your own people’s presence, how rejected candidates are treated.
• Drop sources that have produced no hire in two years, however many applications they bring.
• Test a new source on a single role, not on all of them at once, so you have something to compare against.

Is a referral bonus programme worth it?

Usually yes, and it works better with moderate sums paid after the probation period than with large sums at hiring. The second attracts referrals made out of politeness.

How do I treat speculative applications?

As a separate source, because they say something about your reputation. It is also the source that grows most slowly and most durably.

Where to start

Check whether you record the source for every candidate, and whether it is a field with fixed options. A free-text field produces, in two years, fifty variants of the same source and zero useful reports.

Then take the hires from a year ago and check who is still there. It is the only measurement that counts and can usually be done in twenty minutes with the data you already hold.

The source you cannot buy

In almost any company that has been recruiting for a few years, the best source appears in no budget: people who apply because they heard something good. It cannot be bought, only built — and it can be destroyed far faster than it is built.

The last row is the least obvious and the most powerful in a small market: whoever leaves well becomes, over time, a source of candidates. Whoever leaves badly becomes a source of refusals you will never see in a report.