Churnkey vs ProsperStack: Cancel Flows, Payment Recovery and Pricing Compared

Churnkey and ProsperStack sell the same core product.

A customer clicks "Cancel". Instead of a confirmation page, they get a short flow: why are you leaving, would a pause help, would a cheaper plan fit, here's a discount. Some stay. Both tools also chase failed payments and try to win back customers who left.

So the feature lists overlap. The real differences are how each one charges, which billing systems it connects to, and how it's installed.

This guide goes through those differences. Prices and plan details come from each vendor's own site, last checked on October 30 and 31, 2026. Both vendors also publish their own comparison of the two, linked at the end, and each one makes its own case.

Who Each One Fits

Churnkey fits SaaS teams on Stripe, Chargebee, Maxio, Paddle or Braintree who want a published price, a self-serve trial, and an open-source React SDK if they'd rather build the flow into their own UI.

ProsperStack fits high-volume subscription businesses, in SaaS, ecommerce or digital media, with a retention team that will run several flows and test offers, on one of 14 billing systems.

Churnkey And ProsperStack Compared

How Each One Charges

This is the difference that matters most, because it can flip which tool is cheaper for you.

Churnkey prices by your average monthly churned revenue. Starter is $250 a month, billed yearly, for teams with less than $5k a month in churned revenue. Core and Intelligence are built for teams with $10k or more. Its FAQ says the price is fixed for 12 months and reviewed each year, and that month-to-month billing is available as well as a discounted annual option.

ProsperStack prices by cancellation sessions. A session starts each time a subscriber opens the cancel flow, and a returning subscriber starts a new one. Grow starts at $200 a month with 50 sessions, and each extra 50 costs $75, billed automatically, up to 500 a month. On those list prices, a month with 150 sessions on Grow costs $200 plus two blocks of $75, or $350. Prosper starts at $750 a month with 500 sessions.

So the two models reward different businesses:

• Few cancellations, each worth a lot, is the case per-session pricing handles well. A B2B product where a handful of accounts open the flow each month stays near ProsperStack's base price, however large those accounts are.
• Many cancellations, each worth a little, is the case churned-revenue pricing handles well. A consumer subscription with hundreds of small cancellations can stay on Churnkey's Starter while ProsperStack's session count climbs.

Before either call, pull two numbers from your billing system for the last three months: how many customers started a cancellation, and how much MRR churned. Those two numbers price both tools.

Cancel Flows And Offers

Both build a cancellation flow with a survey, branching steps and offers such as a pause, a plan change or a discount, then apply the accepted offer through your billing system.

Churnkey's plan table lists unlimited cancel flows, including a hosted no-code link, on every plan, Starter included. Core adds A/B testing for cancel flows and payment recovery, unlimited segmentation, and the API, webhook and Slack integrations. Intelligence adds AI features including Adaptive Offers, an Account Agent and AI-powered translations.

ProsperStack's Grow plan includes one customizable cancellation flow, with conditional survey questions, offers and deflection cards. Prosper adds multiple flows, A/B testing of flows and offers, AI Autopilot offers, custom segmentation and CRM or CDP integrations. Enterprise adds unlimited sessions, multi-language support and SSO.

What the customer says in that flow is worth keeping, whichever tool runs it. A cancellation-reason taxonomy decides whether those answers change anything after the flow closes.

Failed Payments

Not every lost customer chose to leave. Some had a card expire.

Churnkey's Payment Recovery is on every plan, Starter included, with unlimited dunning campaigns and what Churnkey calls self-improving retry logic.

ProsperStack's revenue recovery sends dunning emails with offers and card-update links, working alongside your billing system's own retries. Dunning offers are included from Grow.

If failed payments are a large share of your churn, ask each vendor how its retries work with the ones your billing system already runs, so the two don't overlap. The failed-payment recovery guide covers what to check.

After The Customer Leaves

Both run win-backs. Churnkey calls them Reactivation campaigns: emails timed from the cancel reason and other signals, with a return offer applied to the account. ProsperStack includes winback automations with personalized emails and reactivation offers from Grow.

ProsperStack also sells conversion incentives: banners and popups that offer free or trial users a deal to upgrade, priced by monthly active users rather than sessions.

Setup And Billing Systems

Churnkey supports Stripe, Chargebee, Maxio, Paddle and Braintree, and offers a custom integration framework for others. You can send customers to a hosted cancel flow, or build the flow into your own UI with its React SDK. The SDK and its MCP server are open source and free on every plan.

ProsperStack lists 14 billing systems, including Stripe, Chargebee, Recurly, Braintree and Paddle, plus Shopify, Recharge and Bold for ecommerce subscriptions. The flow is embedded in your app and connected to your billing system. Webhooks, Zapier and Slack alerts are on every plan; the API and an MCP server start on Prosper.

If you bill with Recurly or sell subscriptions through Shopify, ProsperStack is the one of the two that lists it.

Picking One

Churnkey is likely the better fit when:

• Less than $5k of revenue churns each month and you want a published price.
• You want to try it this week without a sales call.
• You want an open-source SDK to build the flow into your own UI.

ProsperStack is likely the better fit when:

• Few customers open your cancel flow, but each one is worth a lot.
• You bill with Recurly, Shopify, Recharge or another system Churnkey doesn't list.
• A retention team will run several flows and test offers each month.

Where Cancel Flows Sit In The Journey

A cancel flow is the last chance to change the outcome, and much of what decides it happens earlier, in activation, the trial and the first upgrade. For teams that bill with Stripe, SaaSFunnels runs a cancellation Funnel alongside Funnels for those earlier stages, and counts a save only when Stripe confirms the customer kept paying. It supports Stripe only, so on Chargebee, Recurly or Braintree, one of these two is the better choice. Side-by-side tables are on the Churnkey and ProsperStack comparison pages.

Sources And Further Reading

• Churnkey pricing
• Churnkey Reactivation campaigns
• Churnkey, ProsperStack vs. Churnkey
• ProsperStack pricing
• ProsperStack Stripe integration
• ProsperStack, ProsperStack vs. Churnkey
• ProsperStack docs, flow A/B testing
• SaaS Churn Survey and Cancellation Reasons
• Involuntary Churn and Failed-Payment Recovery
• SaaS Winback Campaign and Customer Reactivation