Last updated: October 20, 2026
The PAX S300 PIN pad was a staple at checkout counters for years. As it is phased out, merchants and the ISOs who support them are moving to the PAX A35 PIN pad, PAX's Android-based multilane replacement.
This guide covers why merchants are switching, what the A35 does better, and a step-by-step rollout plan for ISOs migrating a merchant portfolio from S300 to A35.
The PAX S300: A Reliable Workhorse That Served Its Purpose
For many years the PAX S300 was a dependable choice for retail lanes: reliable, simple to use, and secure for its time. But payment technology moved on. Contactless and mobile wallet volume grew, security standards tightened, and merchants started expecting a modern touchscreen experience at the lane. The S300 was not built for that next phase.
The PAX A35: A Modern Upgrade for Multilane Retail
The PAX A35 is an Android smart PIN pad designed for integrated, multilane retail. It connects to the merchant's POS and gives the customer a modern touchscreen for tap, dip, or swipe. Here are the main reasons merchants are switching.
1. Improved Security
The A35 handles EMV chip transactions, which are more secure than magnetic stripe, and supports end-to-end encryption (E2EE) so cardholder data stays encrypted as it moves through the payment system. It is built to current PCI PIN Transaction Security (PTS) requirements, which helps merchants reduce fraud exposure and stay compliant.
2. Faster Payment Processing
An upgraded processor and modern software make A35 transactions faster than on the S300. In grocery, convenience, and quick-service lanes, shaving seconds off every transaction keeps lines moving.
3. Contactless and Mobile Wallets
The A35 accepts contactless cards and mobile wallets such as Apple Pay, Google Pay, and Samsung Pay. As tap-to-pay keeps growing, a lane that cannot accept it is a lane that frustrates customers.
4. A Modern, Customer-Friendly Interface
Compared with the S300's traditional keypad-and-small-display design, the A35 offers a larger touchscreen with an intuitive interface. Customers find it easier to follow prompts, and cashiers spend less time walking customers through payment.
5. Durability for High-Traffic Lanes
The A35 is designed for busy retail environments where a PIN pad is used hundreds of times a day. A sturdier device means fewer replacements, fewer service calls, and less downtime at the lane.
6. Integration and Flexibility
Because it runs Android, the A35 supports integration with a wide range of POS systems and third-party applications. Merchants and software partners can tailor the payment experience to their workflow instead of working around the device.
7. Ready for What Comes Next
Android-based devices receive software updates and can support new payment methods as they appear, so the A35 is positioned to stay current for years rather than becoming the next S300.
Rolling Out the A35: A 5-Step Plan for ISOs
For ISOs managing a portfolio of S300 merchants, a planned migration avoids disruption and support headaches.
- Assess each merchant's needs and compatibility. Review transaction volume, lane count, and above all whether the merchant's POS and processor support the A35. Confirm certification before you ship hardware.
- Explain the benefits. Merchants comfortable with the S300 may resist change. Lead with what they gain: faster lanes, contactless acceptance, stronger security, and a device that will not be phased out next.
- Train and support. Provide quick-start guides, a short walkthrough for cashiers, and a clear support contact for the first weeks after the swap.
- Plan the deployment logistics. Source devices in volume, stage key injection and app loading ahead of time, and schedule installs around each merchant's slow hours.
- Monitor and collect feedback. Track transaction times and error rates after go-live, and check in with merchants early so small issues do not become cancellations.
Need A35 units in volume for a portfolio migration? Allstar Terminals supplies ISOs, merchant services providers, and processors at wholesale pricing, with no merchant services agreement required. Contact sales@allstarterminals.com or call 888-403-7066.
Having Trouble With an A35 You Already Own?
See our PAX A35 troubleshooting guide for connectivity, settings, app, and hardware fixes.
Conclusion
The S300 earned its place, but the PAX A35 is where multilane retail is going: stronger security, faster transactions, contactless acceptance, and a modern Android platform. For merchants it is an upgrade that pays off at every lane. For ISOs it is a portfolio-wide replacement opportunity worth planning now.
Shop the PAX A35 PIN Pad
