Payment connectivity
EFTPOS & Payment Terminal SIM Cards
Design resilient cellular connectivity for fixed and mobile payment terminals, unattended kiosks and transaction backup links.
In brief
An EFTPOS SIM carries transaction messages between a payment terminal and its approved payment service. The connectivity must be designed with the terminal vendor or acquirer, including APN, addressing, permitted destinations, recovery time and security requirements.
What you can connect
- Retail EFTPOS terminals
- Mobile and pop-up payments
- Unattended kiosks and ticketing
- Backup connectivity for payment gateways
Connectivity is only one part of reliability
A SIM does not make a terminal compliant with payment-industry requirements. The complete solution remains in scope.
Short interruptions can create timeouts, duplicate attempts and poor checkout experiences.
Unrestricted general internet access may be inappropriate for a tightly controlled payment endpoint.
Technical planning
Design the complete connection
Architecture
The terminal normally initiates an outbound encrypted session to an acquirer or payment gateway. Cellular may be primary or a failover path behind a router. The acquirer must approve APN, addressing, DNS, permitted endpoints and recovery behaviour; a SIM by itself does not establish payment compliance.
Data and power sizing
Transaction traffic can be small, but terminal software, diagnostics, receipts, remote support and repeated timeouts change the profile. Measure successful transactions, declined or retried sessions and update windows. Define an alert threshold that detects faults without interrupting legitimate settlement or software traffic.
Solution design
What we qualify before recommending a SIM
Coverage maps and headline data allowances are a starting point. A production design needs the device, traffic, locations and operating model.
- Written terminal and acquirer network requirements
- Latency and recovery testing at representative sites
- Private, dynamic or public/static IP requirements
- Destination allowlists and traffic-policy needs
- Primary versus failover connection design
- Usage alerts, audit records and incident ownership
Multi-provider by design
Choose Onomondo, Telnyx or another fit
Telnyx documents point-of-sale deployments, API-based SIM control, traffic-policy profiles, public static IPs and private routing options; these may align with tightly controlled terminal estates. Onomondo can suit multi-country terminal fleets that value non-steered network choice and network-level diagnostics. Any design remains subject to terminal and acquirer approval.
Telnyx traffic-policy profiles and documented point-of-sale use case make it a natural controlled-estate candidate. Onomondo can suit multi-country fleets where local network choice and remote packet diagnostics matter. The final service remains conditional on written terminal-vendor and acquirer acceptance.
Availability note: networks, radio technologies, IP features, regions and platform controls vary by provider, country and plan. We verify the proposed configuration during the pilot.
Primary product sources reviewed 26 July 2026:
What the pilot should prove
- Confirm written acquirer network and addressing requirements.
- Test transaction latency, failure and recovery at representative sites.
- Exercise primary-to-cellular failover and return-to-primary.
- Validate allowlists, usage alerts, updates and incident ownership.
Discover
Confirm devices, sites, traffic, security, support and commercial constraints.
Pilot
Test representative hardware and locations, then measure attachment, usage and recovery.
Scale
Document the approved profile, alerts, ownership and rollout or rollback process.
Frequently asked questions
Is a payment SIM PCI DSS compliant?
A SIM alone is not a PCI DSS-certified payment solution. Compliance depends on the terminal, applications, network design, processes and organisations handling payment data.
Do EFTPOS terminals need a static IP?
Many use outbound connections and do not. Some acquirers or network designs require stable addressing or allowlists, so the terminal specification decides.
Can cellular be used as an NBN backup for payments?
Yes, with a compatible router or terminal, but failover detection, DNS, addressing and recovery should be tested end to end.
How much data does EFTPOS use?
Transaction messages are often small, but software updates, diagnostics and ancillary services change the total. Measure a representative terminal over a pilot period.
Can you restrict what a terminal can reach?
Provider options may include private routing or network traffic policies. We confirm the required destinations, protocols and chosen platform capabilities.
Prove the connection before you scale it.
Tell us what you are connecting, where it operates and what must happen when coverage changes. We will shape a representative iSIM pilot.