How to Calculate Source Effectiveness in Internal HR – and Why It Matters

Hiring isn’t just about finding talent—it’s about finding the right talent through the right channels. In-house HR teams juggle multiple recruiting partners, job boards, and referral programs, but without clear data, it’s hard to know what’s really working.

That’s why tracking Source Effectiveness is so powerful. It helps you identify which recruiting sources are bringing in high-quality hires—not just filling roles.

Hiring the right people is one thing—hiring them efficiently is another. For in-house HR teams juggling multiple recruitment sources, one key question remains:

Which recruiter or channel actually delivers the best return on investment?

That’s where Source Effectiveness comes in. It’s a powerful metric that tells you which of your hiring sources are delivering quality hires, not just filling seats.

In this post, we’ll break down how to calculate source effectiveness, why it matters for your recruitment strategy, and share a real-world example where one agency—Bastian—stood out from the crowd.

What Is Source Effectiveness?

Source Effectiveness measures how well a recruitment channel performs in delivering high-quality, long-term hires. It’s not just about how many people you hire—it’s about how many of those hires actually work out.

A “quality hire” usually meets criteria such as:
Successfully completing probation
Strong performance reviews in the first 6–12 months
Staying with the business beyond a year
Fitting well with the company’s culture and values

Why Should Internal HR Teams Track Source Effectiveness?

Tracking this metric allows you to:
Optimise your recruitment spend
Identify your top-performing recruiters
Reduce time-to-hire and turnover
Make smarter, data-led hiring decisions

It’s the difference between guessing and knowing what’s working.

How to Calculate Source Effectiveness

Here’s a straightforward formula you can use:
📊 Source Effectiveness (%) = (Number of Quality Hires / Total Candidates from Source) × 100

You can also calculate cost-effectiveness:
💰 Cost per Quality Hire = Total Cost of Source / Number of Quality Hires

Example:

Let’s say you’re a Talent Acquisition Manager in the logistics sector. Over six months, you’ve worked with three recruitment agencies to fill roles for supply chain coordinators.

Here’s how they performed:

✅ Calculating Source Effectiveness:
Bastian: (9 / 25) × 100 = 36%
Recruiter A: (5 / 40) × 100 = 12.5%
Recruiter B: (4 / 35) × 100 = 11.4%

💵 Calculating Cost per Quality Hire:
Bastian: $450,000 / 9 = $50,000
Recruiter A: $650,000 / 5 = $130,000
Recruiter B: $600,000 / 4 = $150,000

Key Takeaway:

Although Bastian submitted fewer candidates than the others, they delivered nearly twice the number of quality hires—at a significantly lower cost per hire.
That’s what true recruitment ROI looks like.

How to Start Measuring Source Effectiveness in Your Team

Define what quality hire means for your business
(probation success, early performance, retention, etc.)
Ensure every candidate in your ATS has a tagged source
Track outcomes quarterly and review trends over time
Use the data to refine your sourcing strategy and partner list

Final Thoughts

Hiring shouldn’t be a guessing game. Measuring source effectiveness gives HR leaders the clarity to invest in what’s working—and cut what’s not.

Whether you’re scaling fast or aiming to improve retention, sourcing data like this helps you make smarter, faster, and more cost-effective recruitment decisions.

And if you’re looking for a recruitment partner that consistently delivers top-tier results?

Bastian is leading the way.