Accelerators and Tiers in Spiff: How to Build Them Correctly

Accelerators are the part of a commission plan that pays reps a higher rate once they hit a certain attainment threshold — typically 100% of quota. A rep who hits 120% of quota should earn more per dollar of revenue than one who hits 95%. Done right, this drives the right behaviour. Done wrong in Spiff, it produces commission statements that are either too high, too low, or inconsistent — and reps notice immediately.

The Two Types of Accelerator Structure

Before building anything in Spiff, you need to be clear about which type of accelerator structure you're implementing. The two most common are fundamentally different in how they calculate payout above quota.

Marginal (incremental) tiers

Each tier rate applies only to the revenue within that tier — similar to how income tax brackets work. A rep earning above 100% quota gets the base rate on the first 100% of quota, and the accelerated rate only on the revenue above that threshold.

Retroactive (cliff) tiers

Once a rep crosses an attainment threshold, the higher rate applies retroactively to all revenue — including the revenue below the threshold. This is more generous and creates a stronger pull effect near the threshold, but it means commission amounts can jump significantly when a rep crosses a tier boundary.

A Typical Tiered Accelerator Structure

Here's an example of a three-tier accelerator plan as it might be set up for a SaaS AE:

Attainment band	Commission rate	Structure
0% – 74%	6%	Below threshold — reduced rate
75% – 99%	8%	Standard rate
100% – 124%	10%	First accelerator tier
125%+	14%	Second accelerator tier — stretch

Whether each tier is marginal or retroactive is the key design decision. Most plans use marginal tiers for the lower bands and a retroactive bump at the stretch tier — but whatever you choose, it needs to be explicit in the policy and mirrored exactly in the Spiff configuration.

How to Build Tiers in Spiff: The Key Decisions

Attainment-based vs revenue-based triggers

Tiers can be triggered by attainment percentage (rep hits 100% of quota) or by an absolute revenue amount (rep closes $500k). Attainment-based tiers are more common for quota-carrying roles because they work fairly across reps with different quota sizes. Revenue-based triggers are sometimes used for overlay roles or SPIFFs. Make sure Spiff is configured to trigger tiers the same way your policy defines them.

Cumulative vs period-based calculation

Does the accelerator apply based on cumulative attainment across the full year, or is it reset each quarter? A rep who hits 130% of their Q1 quota benefits from the stretch accelerator in Q1 — but do they start Q2 at zero again? Annual cumulative plans are more motivating late in the year but harder to model. Quarterly resets are cleaner and more predictable. Either can be built in Spiff, but the configuration is different and it must match your policy.

The kicker vs the multiplier

Some plans don't use tiered rates — they use a multiplier applied to the total commission once attainment crosses a threshold. For example: earn standard commission all year, then if you hit 120% of annual quota, your total commission is multiplied by 1.25. This is called an annual kicker or multiplier. Spiff can handle this but it requires a specific configuration approach — it's not the same as building standard tiers.

Testing Your Accelerator Plans Before Go-Live

Accelerator configurations are the most likely place for silent errors — calculations that look right in the UI but produce wrong outputs for specific attainment scenarios. Before any rep sees their statement, test these specific scenarios manually:

• A rep at exactly 100% attainment — the tier boundary. Verify the rate applied is correct and consistent with your policy.
• A rep at exactly a tier boundary — e.g. exactly 125%. Does the calculation use the lower tier rate or the upper? This edge case is where marginal vs retroactive ambiguity surfaces.
• A rep who crosses a tier mid-deal — they're at 95% attainment, then close a large deal that takes them to 118%. Which deals get the accelerated rate?
• A rep with a quota change mid-period — attainment percentages need to reflect the correct quota for each sub-period.
• A rep at 0% attainment — verify the plan handles edge cases at the bottom of the range cleanly, particularly if there's a below-quota reduced rate.

The Overlap With Clawbacks

If your plan includes both accelerators and clawbacks — which Storyblok's did — you need to define how they interact. If a rep earned a deal at the 125% tier (14% rate) and that deal then churns and triggers a clawback, is the clawback calculated at the 14% rate they were paid, or the 8% base rate? This needs to be in the policy and mirrored in the Spiff configuration. Most companies use the rate at which the commission was originally paid, but it needs to be explicit.