SaaS Finance KPIs Every Founder Should Track (MRR, ARR, CAC, LTV, Churn)

Every SaaS founder has a dashboard. Fewer have one; they would defend it line by line in a diligence call. The usual story: MRR comes from a billing export, churn from a spreadsheet someone built two years ago, and CAC from whatever marketing spend was easy to find. Each number looks fine on its own. Put them next to the income statement, and they stop agreeing.

That gap matters more than most founders expect. Investors, lenders, and acquirers price a SaaS company off these metrics, and they will check them against the books. This guide covers the ten KPIs worth tracking, how to calculate each one, what good roughly looks like, and how to keep them tied to numbers you can prove.

To keep it concrete, we'll use one fictional company throughout: a B2B SaaS business that starts the month with 400 customers paying an average of $200 a month.

1. Monthly recurring revenue (MRR)

What it is: the normalized monthly value of all active recurring subscriptions. One-time setup fees, services, and most usage overages stay out. Annual plans count at one-twelfth of their value per month.

How to calculate: sum each active customer's recurring monthly fee, after discounts. Our company starts at 400 × $200 = $80,000 MRR.

The single total hides most of the story, so track the MRR bridge: what you started with, what was added, and what was lost.

Net new MRR was $5,600, but the bridge shows $3,400 leaking out through downgrades and cancellations. That leak is invisible if you only watch the total.

pilots,

2. Annual recurring revenue (ARR)

What it is: the annualized value of your recurring base. How to calculate: MRR × 12. Our company ends the month at $85,600 MRR, or $1,027,200 ARR.

ARR is the headline number in most fundraising and valuation conversations, which is exactly why it gets stretched. Signed contracts that haven't started, one-time fees, pilots, and expected usage don't belong in it. If you report a version that includes any of those, give it a different name ("contracted ARR," say) and keep the definition fixed. That is also the standard public companies are held to: the SEC's 2020 guidance on key performance indicators expects a clear definition of each metric, an explanation of how it's calculated, and disclosure when the method changes. It's a good habit long before you're public.

3. Customer (logo) churn

What it is: the share of customers who cancel in a period. How to calculate: customers lost ÷ customers at the start of the period. Our company lost 12 of 400 customers, so monthly logo churn is 3%.

Be careful annualizing it. Three percent a month is not 36% a year; it compounds to roughly 31% of the starting customers gone after twelve months (1 − 0.97¹²). Also decide up front how you treat customers on paused accounts or failed payments, and stick with it, because a quiet definition change is one of the easiest ways for churn to “improve.”

4. Revenue retention: GRR and NRR

Logo churn counts customers. Revenue retention counts dollars, which is what investors care about most.

• Gross revenue retention (GRR): (starting MRR − contraction − churned MRR) ÷ starting MRR. It ignores expansion, so it can never exceed 100%. Our company: ($80,000 − $1,000 − $2,400) ÷ $80,000 = 95.75% for the month.
• Net revenue retention (NRR): (starting MRR + expansion − contraction − churned MRR) ÷ starting MRR. Our company: $79,600 ÷ $80,000 = 99.5% for the month.

Most companies report both on a 12-month cohort basis: take the customers you had a year ago and compare what they pay today with what they paid then, excluding anyone new. NRR above 100% means your existing customers grow faster than they shrink, so growth compounds even before new sales.

What good looks like: it varies a lot by customer size. For a reference point, SaaS Capital's 2026 survey of more than 1,000 private B2B SaaS companies put median NRR at 103% and median GRR at 91% for bootstrapped companies with $3M to $20M ARR, with the top 10% reaching about 118% and 100%. Enterprise-focused companies usually sit higher, and SMB-focused ones lower.

5. Customer acquisition cost (CAC)

What it is: the average sales and marketing cost to win one new customer. How to calculate: total sales and marketing expense in the period ÷ new customers won.

Our company spent $45,000 on sales and marketing in the month and won 30 new customers, so CAC is $1,500.

The most common mistake is counting only ad spend. A fully loaded CAC includes sales and marketing salaries and commissions, contractor fees, tools, and agency costs. Pull those from the income statement, not from the ad platform. If your sales cycle is long, compare spend with customers who won a month or a quarter later, and use the same lag every time.

6. Customer lifetime value (LTV)

What it is: the gross profit you expect from an average customer before they churn. How to calculate: (average revenue per account × gross margin %) ÷ monthly churn rate.

Our company: ($200 × 80%) ÷ 3% = $160 ÷ 0.03 = about $5,333.

Two cautions. Use gross margin, not revenue, or LTV will be overstated by 20% or more. And treat LTV as an estimate: at very low churn the formula produces huge numbers that assume customers stay for decades. Many finance teams cap the lifetime at five years to keep it honest.

7. LTV to CAC ratio

How to calculate: LTV ÷ CAC. Our company: $5,333 ÷ $1,500 = about 3.6 to 1.

What good looks like: a ratio around 3 to 1 is the commonly cited target. Well below that, you're paying too much to acquire customers or losing them too quickly. Far above it can mean you're underinvesting in growth. Because both inputs are estimates, read the trend over several quarters rather than any single month.

8. CAC payback period

What it is: how many months of gross profit it takes to earn back what you spent to win a customer. How to calculate: CAC ÷ (average new-customer MRR × gross margin %).

Our company: $1,500 ÷ ($200 × 80%) = about 9.4 months.

Payback is often more useful than LTV to CAC because it doesn't depend on guessing how long customers stay, and it tells you directly how much cash growth ties up. Under 12 months is generally seen as strong for SMB-focused SaaS; enterprise companies with bigger contracts often run 18 months or more.

9. Gross margin

What it is: the share of revenue left after the cost of delivering the service. How to calculate: (revenue − cost of revenue) ÷ revenue.

For SaaS, cost of revenue usually includes hosting and infrastructure, third-party software built into the product, customer support and onboarding staff, and payment processing fees. Software companies commonly target 75% to 80% or better. The catch is classification: if hosting sits in "software subscriptions" and support salaries sit in general overhead, gross margin looks great, and every metric built on it (LTV, payback) is overstated. Getting this right is a chart-of-accounts decision, made once.

10. Burn rate, runway, and burn multiple

• Net burn: cash out minus cash in for the month.
• Runway: cash in the bank ÷ average monthly net burn. Use a three-month average so one large annual prepayment doesn't make the runway look longer than it is.
• Burn multiple: net burn ÷ net new ARR for the same period. It shows how many dollars you spend to add one dollar of ARR. Lower is better; many investors treat anything under about 2 as efficient for an early-stage company.

Annual prepayments deserve a note here too. A customer paying $24,000 upfront improves cash and runway immediately, but the revenue arrives over twelve months. That's healthy, but it means a cash-strong quarter can hide weak bookings, so look at burn and net new ARR together.

The 10 SaaS KPIs at a glance

payments,

Where SaaS metrics and the books drift apart

Every number above should trace back to something in your accounting system. When it doesn't, these are the usual reasons:

• MRR built from billing data that never reconciles. Credits, refunds, failed payments, and manual invoices sit outside the billing tool. Reconcile MRR to subscription revenue each month and explain the difference.
• Revenue booked when cash arrives. If annual plans hit revenue in the month they're paid, your income statement and your MRR tell completely different stories. Under ASC 606, that prepayment is deferred revenue, recognized month by month.
• CAC from partial spend. Salaries and commissions sitting in general payroll instead of sales and marketing make CAC look cheap.
• Cost of revenue misclassified. Hosting and support in overhead inflate gross margin, LTV, and payback all at once.
• Definitions that drift. Changing how churn or ARR is calculated without saying so is the fastest way to lose an investor's trust.

The fix is boring but effective: close the books every month, then calculate the KPIs from reconciled numbers using written definitions. A month-end close that includes a deferred revenue roll-forward and an MRR-to-revenue reconciliation is what makes the dashboard defensible. If your close isn't there yet, that's the first job for an outsourced bookkeeping team.

When to bring in help

A founder can run this dashboard in a spreadsheet for a long time, as long as the books underneath it are clean. The picture changes when you're preparing for a raise or a lender, when the board wants cohort analysis, or when nobody can explain why MRR and revenue moved differently last quarter. At that point, you need someone who will build the definitions, tie every number to the ledger, and tell you which lever to pull.

That's what fractional finance support is for. If you're weighing it, our guide What Is a Virtual CFO and Does My Business Need One? covers when it makes sense. Our virtual CFO services build and run KPI dashboards from reconciled books, and our accounting services for SaaS companies cover the MRR, ARR, churn, and unit economics reporting that sits underneath them.

→  Virtual CFO services: KPI dashboards and board reporting

→  Accounting services built for SaaS companies