How expensive is hitting service level agreements?
№ 200 · Cost per SLA-met unit
Definition
MetricTotal operating cost divided by the number of units delivered inside the service level agreement
Unitcurrency per SLA-compliant unit, and the multiple over raw cost per unit
Cost divided by units delivered within SLA. Build by filtering volume to on-time units and dividing total cost by that. Reveals the real cost of meeting commitments (vs. just total cost / total volume). Example: $5.80/unit if you only count on-time delivery (vs. $4.20 blended).
- SLA
- Service level agreement. Contracted response or resolution time. Measured as percent of tickets resolved inside the promised window.
Benchmarks
| Bottom 30% | Median | Top 30% |
|---|---|---|
| 1.25 times raw cost per unit or worse, attainment below 80% | 1.10 to 1.18 times raw cost per unit, corresponding to 85% to 91% attainment | 1.02 to 1.06 times raw cost per unit, corresponding to 95%+ SLA attainment |
Composite metric constructed from two measured inputs: cost per unit and SLA attainment rate. Absolute anchors for customer operations put agent-assisted cost per contact at 13.50 to 15.56 USD before adjustment, which becomes roughly 15 to 18 USD per SLA-met contact at median attainment. For fulfilment, all-in cost per order of 10 to 17 USD becomes 11 to 20 USD per on-time order at median attainment. US and Western Europe cost base, 2024 to 2026. · No publisher benchmarks this metric directly. It is a constructed ratio and the bands above are derived arithmetically from published cost-per-unit figures and published SLA attainment figures, not observed as a distribution. That construction is the honest way to use the chart: the multiple over raw cost per unit is the informative part, because it isolates the cost of the units that missed. Two definitional warnings. First, the cost-per-contact sources disagree by roughly a factor of two (13.50 USD Gartner median against 8 to 12 USD global average) and the driver is geography and channel mix, not efficiency. Second, whether breach penalties belong in the numerator is a choice, and it materially changes the answer where contractual penalties exist, for example the 3% of cost of goods sold that Walmart charges suppliers per on-time in-full failure.
Category split omitted: The metric is a constructed composite that no publisher reports, so no category split of it exists to draw on.
When it looks bad
Raw cost per unit is flat or falling while cost per SLA-met unit rises, so the widening wedge between the two lines is money being spent on units that missed the promise.
Cost per order holds at 12.40 all year while attainment slides from 94% to 82%. Cost per SLA-met order goes 13.19 to 15.12, a 15% rise that never appears on the cost line.
What to do about it
- Plot cost per unit and cost per SLA-met unit on the same axis and manage the wedge between them. The wedge is the exception cost, and it is the only figure that moves when the tail is fixed rather than the average.
- Put the contractual breach cost into the numerator where one exists. Walmart charges 3% of cost of goods sold per on-time in-full failure, so for suppliers into that programme the SLA miss is already priced and leaving it out understates the true cost per compliant unit (Red Stag, citing Walmart supplier terms).
- Convert the target from an average to a percentile, for example 95% of units inside SLA rather than an average transit or handle time. Contact centres have used 80% answered within 20 seconds for decades precisely because averages conceal the tail that drives cost (Verint Workforce Management Study, 2024).
- Segment expedite and recovery spend by root cause and cap it per cause. If expedites are buying attainment, cost per SLA-met unit rises even as attainment improves, and exposing that trade is the main reason to run this chart rather than a simple service level chart.
Sources
- MetricNet Defines cost per contact and average speed of answer as separate scorecard KPIs weighted at 25% and lower respectively, and states explicitly that a low price per contact is not good if achieved by sacrificing service levels. Quartile values in the public sample are redacted. metricnet.com ↗
- MetricNet and Gartner, reported by Atidiv MetricNet average cost per ticket 15.56 USD. Gartner reports a median of 13.50 USD per assisted contact for US-based support. Global average across all industries, countries and channels 8 to 12 USD. atidiv.com ↗
- Gartner, published by University of Wisconsin-Madison DoIT Gartner cost per contact 17.90 USD mean in 2020 and 19.80 USD median in 2021 for medium environments, with first contact resolution at 74% then 71% and abandonment 5.1% then 4%. Flagged as pre-2023 data. it.wisc.edu ↗
- Warehousing Education and Research Council, reported by Hyster-Yale Best-in-class on-time shipments 99.2% or better, down from 99.5% the prior year. This is the attainment denominator for a fulfilment version of the metric. scg-lm.s3.amazonaws.com ↗
- Verint, reported by Helpable The contact centre industry standard service level is 80% of contacts answered within 20 seconds, a percentile commitment rather than an average, which is the correct denominator shape for this metric. gethelpable.com ↗
- Red Stag Fulfillment, citing Walmart supplier terms Walmart charges suppliers 3% of the cost of goods sold for each on-time in-full failure, which converts an SLA miss into a directly measurable cost that belongs in the numerator. redstagfulfillment.com ↗
- MRPeasy OTIF of 95% to 99% is considered excellent in most industries; a poor score falls below 85%. These are the attainment bands used to derive the multiples above. mrpeasy.com ↗
- Eightx All-in DTC fulfilment cost per order 10 to 17 USD by vertical in 2026, which is the cost numerator before SLA adjustment. eightx.co ↗