Churnkey and Churn Buster show up in almost every "best Stripe dunning" shortlist. Both have strong reputations, both integrate deeply with Stripe, and both solve real problems for SaaS operators. But they aren't the same tool, and the market around them has shifted.
Churn Buster was reportedly acquired by Recurly in 2022 and has since been positioned closer to Recurly's broader subscription platform. Churnkey has continued to grow as an independent retention suite with a focus on cancel flows plus dunning. If you're picking between them today, the answer depends on what you actually need.
This is a practical comparison for SaaS teams on Stripe, with an honest note on where a leaner option like Rekko fits.
At a glance
| Factor | Churnkey | Churn Buster (Recurly) | Rekko |
|---|---|---|---|
| Core focus | Retention suite (dunning plus cancel flows) | Dunning, retention tooling | Focused dunning |
| Starting price | Around $100 to $200/mo | Custom, often enterprise-tier | $29/mo flat |
| SMS support | No | Limited | Yes |
| Cancel flows | Yes | Partial | No |
| Setup time | Half a day to a day | Hours to days | About 5 minutes |
| Best for | Mid-market SaaS wanting retention + dunning | Teams in the Recurly orbit | SMB to mid-market wanting focused recovery |
Churnkey in practice
Churnkey positions itself as a complete retention platform. You get failed payment recovery, but also cancel flows with offers and surveys, customer health scoring, payment method capture forms, and A/B testing across sequences.
For a growing SaaS, this means one tool handles two distinct problems:
- Involuntary churn: Cards fail, customers don't update, subscriptions cancel
- Voluntary churn: Customers click "cancel," and you need a chance to save them
Churnkey's cancel flow is a real feature. When a customer tries to cancel, you can show tailored offers (pause, downgrade, extend trial), gather survey data on why they're leaving, and try to save the sub. Operators report saving 15% to 30% of cancels with well-tuned flows.
On the dunning side, Churnkey handles the usual: email sequences, card update links, retry logic. Email only, no native SMS as of this writing.
Pricing is custom and scales with MRR. Expect $100 to $200/mo for smaller teams, $300 to $500/mo once you're in mid-market territory, and quotes above that for larger setups. Some plans historically included a percentage on recovered revenue, so it's worth asking for the full pricing structure.
Churn Buster in practice
Churn Buster was one of the original Stripe dunning tools, launched around 2014. It built a reputation for clean email sequences, pre-dunning for expiring cards, and solid recovery rates.
After the reported 2022 acquisition by Recurly, Churn Buster's positioning has tilted toward Recurly's broader subscription platform. It still works with Stripe, but net-new customers often find themselves in conversations about Recurly's full billing stack rather than Churn Buster as a standalone product.
For teams already using Recurly, this integration is a plus. For Stripe-only SaaS looking for a standalone dunning tool in 2026, the path is less obvious than it used to be. If you're evaluating Churn Buster today, it's worth asking directly whether you can sign up as a standalone Stripe customer and what pricing looks like.
Feature depth comparison
| Feature | Churnkey | Churn Buster | Rekko |
|---|---|---|---|
| Email dunning sequences | Yes | Yes | Yes |
| SMS dunning | No | Limited | Yes |
| Pre-authenticated update links | Yes | Yes | Yes |
| Pre-dunning (expiring cards) | Yes | Yes | Yes |
| Cancel flows | Yes | Partial | No |
| A/B testing | Yes | Yes | No |
| Cohort analytics | Yes | Yes | Basic |
| Stripe-only setup | Yes | Yes | Yes |
If you want a full retention suite with cancel flows and A/B testing, Churnkey is the most complete of the three. If you want deep integration with a billing platform, Churn Buster via Recurly is a path. If you want focused dunning without the extra surface area, Rekko is the leanest option.
Pricing reality check
Let's put rough numbers against each tool for a $100K MRR SaaS losing 9% ($9K/mo) to failed payments.
Churnkey: Likely $200 to $400/mo for this size. Mid-range recovery via email-only dunning might pull back 50% to 60% of that ($4.5K to $5.4K). Cancel flows add incremental saves on voluntary churn, which is the real value-add at this tier.
Churn Buster: If you can sign up standalone, pricing historically landed in the $100 to $300/mo range. Similar recovery profile to Churnkey on the dunning side, minus the cancel flow depth.
Rekko: $49/mo on the Essential plan. Email plus SMS sequences push recovery into the 60% to 80% range, meaning $5.4K to $7.2K recovered. Your cost is a fixed $49 plus SMS usage.
This isn't a case of "one is objectively cheaper." Churnkey's cancel flows add value Rekko doesn't replicate. But if your only problem is failed payments, paying retention-suite prices for a dunning-only feature set is overkill.
Setup speed
- Churnkey: Expect half a day to a full day of setup for the full suite. Cancel flows need design decisions, offer logic, and template work.
- Churn Buster: Traditionally a few hours for Stripe-connected dunning. Post-acquisition the path may be longer.
- Rekko: OAuth into Stripe, pick a sequence template, tweak copy, live in about 5 minutes.
If you're in "we're bleeding MRR and need this live today" mode, setup speed matters.
When each one wins
Pick Churnkey if
- You're above $250K MRR
- You want cancel flows, not just dunning
- You have the budget for a retention suite ($200 to $500/mo range)
- A/B testing and cohort analytics are real requirements for you
Pick Churn Buster if
- You're already using or considering Recurly
- You want a mature Stripe dunning tool with a known track record
- You're fine navigating the post-acquisition product direction
Pick Rekko if
- You only need focused dunning, not a full retention suite
- You want email plus SMS in one tool without enterprise pricing
- You're on Stripe and want to stay there
- Flat, predictable pricing matters more than advanced features you won't use
The honest take on "leaner"
Most SaaS teams under $500K MRR don't need A/B testing on their dunning emails. They need the dunning to exist and work. The biggest recovery rate jumps come from two things: adding SMS to the sequence, and sending recovery messages faster than Stripe's default retry schedule. Both of these are core Rekko features and don't require a retention-suite subscription to access.
If you're at the stage where cancel flows, offer logic, and deep cohort analytics move the needle, go with Churnkey. If you're not there yet, paying $300/mo for features you won't configure is a tax on being well-marketed to.
Final call
Churnkey is a strong retention suite for mid-market SaaS. Churn Buster has a history but a more uncertain standalone path. Rekko is the focused, flat-fee choice if you want Stripe-native dunning with email plus SMS and nothing you don't need.
Start your 14-day free trial, no credit card required. You can also compare directly on our Churnkey alternative and Churn Buster alternative pages.