SLA (Service Level Agreement): Definition and Meaning

What does SLA stand for?

SLA stands for Service Level Agreement. It’s a contract, formal or informal, that defines what one party will deliver to another, how performance will be measured, and what happens when targets are missed.

The concept originated in IT service management. The ITIL framework defines an SLA as “an agreement between an IT service provider and a customer” that “describes the IT service, documents service level targets, and specifies the responsibilities of the IT service provider and the customer.”¹ ISO/IEC 20000-1:2018, the international standard for IT service management, codifies service level management as a core requirement for any certified service management system.²

But SLAs aren’t just for IT anymore. In B2B revenue operations, the term has been adopted to describe the internal agreement between marketing and sales: the handoff rules that determine how leads get qualified, routed, and followed up on.

How SLAs work in revenue operations

In a RevOps context, an SLA typically governs the marketing-to-sales handoff. It answers two questions:

What does marketing owe sales? A specific volume or quality of qualified leads, typically MQLs or SQLs, delivered per period. The SLA defines the qualification criteria (what counts as an MQL) and the volume target (how many per month).

What does sales owe marketing? A commitment to follow up on qualified leads within a defined timeframe. The most common target is response time: sales must attempt contact within four business hours of receiving an MQL. Speed matters here. Research consistently shows that lead conversion rates drop sharply after the first hour of inactivity.

Why write this down instead of just… talking about it? Because without a documented agreement, accountability disappears. Marketing can claim success by pointing at MQL volume while sales ignores half the leads. Sales can blame lead quality while cherry-picking only the easiest opportunities. An SLA forces both sides to commit to measurable targets.

SLA vs. KPI

These terms get confused constantly, but they’re different things.

A KPI (Key Performance Indicator) is a metric you track to measure performance. Lead response time, MQL-to-SQL conversion rate, and customer satisfaction score are all KPIs.

An SLA takes a KPI and attaches a commitment. “We track lead response time” is a KPI. “Sales will respond to every MQL within four business hours, and if they don’t, the lead gets reassigned to another rep” is an SLA.

You can track KPIs without having SLAs: you’re measuring performance but not committing to a standard. SLAs without underlying KPIs don’t work. You need a measurable metric to determine whether the agreement is being met.

What belongs in a marketing-sales SLA

If you’re building an internal SLA between marketing and sales for the first time, keep it simple. Cover these four things:

• Lead definition. What qualifies as an MQL? What criteria must a lead meet before it gets routed to sales? This is the single most important element. If marketing and sales don’t agree on what a “qualified lead” means, every other part of the SLA falls apart.
• Volume commitment. How many qualified leads will marketing deliver per month or quarter? This gives sales pipeline predictability and gives marketing a clear target.
• Response time. How quickly must sales follow up after receiving a qualified lead? Four business hours is a common benchmark, but the right number depends on your sales cycle and deal complexity.
• Review cadence. How often do both teams sit down to review SLA compliance and adjust the terms? Monthly is standard. The SLA should be a living document, not something you set and forget.

What doesn’t belong in a v1 SLA: penalty clauses, escalation matrices, exception workflows, and other bureaucratic weight. Start with a one-page agreement that both teams actually read and reference. You can add complexity later if you need it.

Frequently Asked Questions

What does SLA stand for?

SLA stands for Service Level Agreement. It is a formal or semi-formal agreement between two parties (a service provider and a customer, or two internal teams) that specifies what service will be delivered, the metrics used to measure performance, and what happens if targets are missed. In B2B companies, SLAs appear in two main contexts: externally between a vendor and customer (e.g., guaranteed 99.9% uptime for a SaaS product) and internally between departments like marketing and sales (e.g., sales will follow up on every MQL within four business hours).

What is the difference between an SLA and a KPI?

A KPI (Key Performance Indicator) is a metric you track. An SLA is a commitment you make. KPIs measure how you're performing: conversion rate, response time, uptime. SLAs take specific KPIs and attach a target and consequences: if response time exceeds four hours, the lead gets reassigned. You can have KPIs without SLAs (you're tracking but not committing), but you can't have an SLA without at least one underlying KPI to measure compliance.

Do small teams need a formal SLA?

You don't need a twenty-page legal document, but even a two-person marketing-and-sales setup benefits from a written agreement on lead handoff rules. Without one, the same argument repeats every quarter: marketing says they're generating plenty of leads, sales says the leads are garbage, and nobody has a shared definition of what 'good' looks like. A one-page internal SLA that defines lead qualification criteria, response time expectations, and a monthly review cadence removes the guesswork. It gives both sides something concrete to optimize against.