Outsourcing sales development can be a game-changer for UK businesses that want to scale pipeline without the cost of building an in-house team. But success depends on tracking the right KPIs. Without clear metrics, you risk paying for activity that looks busy on paper but contributes little to revenue. The key is measuring what really matters: the indicators that show whether your outsourced SDRs are creating genuine business value.
Foundation Metrics Every Business Should Track
Response rates are the first benchmark. Across email, LinkedIn, and cold calling, your outsourced SDRs should generate consistent engagement. For email, a healthy response rate sits between 2-5%. LinkedIn connection acceptance rates typically fall around 20-30%, while cold calls should yield meaningful conversations in 1-2% of attempts. These numbers show whether your targeting and messaging resonate with your market. If they fall short, it’s usually a sign that the strategy needs adjusting.
Lead qualification accuracy is another critical measure. A strong outsourced team should deliver 80%+ accuracy against your ideal customer profile. If the qualification rate dips, it wastes sales team time and signals either poor understanding of your requirements or gaps in training. Meeting booking rates are equally important. Quality SDRs should be able to convert 10-15% of qualified leads into meetings, with show-up rates consistently above 70%. These metrics show whether prospecting activities are actually translating into opportunities.
Advanced Metrics That Separate Good from Great
Beyond the basics, advanced KPIs highlight whether your outsourced SDRs are truly driving revenue impact. Pipeline velocity is one of the most telling. By tracking the time it takes to move from first contact to meeting booked, and from meeting to qualified opportunity, you can see if your outsourced team is speeding up sales cycles or slowing them down. Faster movement usually signals stronger lead quality and effective messaging.
Channel performance is another layer to monitor. Different industries and decision-makers respond differently to email, LinkedIn, phone, or website visitor identification. Analysing conversion rates across channels will reveal where to focus time and budget. Cost per qualified lead ties these efforts back to commercial outcomes. Divide the full cost of outsourcing — including tools, subscriptions, and management — by the number of qualified leads delivered. This gives a true comparison point against in-house teams or alternative marketing investments.
Quality Indicators That Protect Your Brand
While activity and pipeline metrics are essential, brand protection matters too. Email deliverability is a prime example. Poor practices can hurt your domain reputation, so track deliverability rates (keep them above 95%) and unsubscribe rates (below 0.5%). Sentiment tracking also helps. Negative or dismissive responses may suggest overly aggressive messaging or weak targeting. A healthy programme generates neutral-to-positive replies even when prospects aren’t ready to buy, protecting long-term brand perception.
Compliance must not be overlooked. With GDPR and other regulations, your outsourced SDRs need to respect opt-outs, manage data properly, and document processes. Regular compliance checks reduce risk and ensure sustainable prospecting.
Setting Realistic Benchmarks
Industry context is crucial when setting targets. SaaS companies, for example, will see different norms than professional services or manufacturing. Average deal size, buying cycles, and decision-making complexity all influence what “good” looks like. Ramp-up periods also matter. Don’t expect peak performance immediately. Allow 4-6 weeks for onboarding, testing, and optimisation, with progressive targets that build towards consistent results.
Making Data Actionable
The most successful outsourced SDR programmes build regular review and feedback loops. Weekly reviews should focus on trends in activity and engagement, while monthly reviews dive deeper into targeting, messaging, and channel allocation. Quarterly assessments should link SDR activity back to ROI and pipeline contribution. Crucially, feed back insights from your sales team. Tracking which booked meetings turn into closed deals helps align SDR efforts with actual revenue impact, not just activity.
The Bottom Line
Outsourced SDR partnerships succeed when you measure what truly drives growth. Response rates, qualification accuracy, and meeting conversion provide the foundation, while advanced KPIs like pipeline velocity and cost per qualified lead reveal deeper performance. Brand safeguards like deliverability, sentiment, and compliance keep your long-term reputation intact. When tracked consistently and reviewed collaboratively, these KPIs ensure your outsourced SDRs feel like a seamless extension of your team — one that contributes measurable growth to your sales pipeline.
