Choosing the Right Satellite Airtime in 2026: A Practical Guide to Staying Connected Anywhere

When you invest in a satellite phone, tracker, or hotspot, the device itself is only half the story. Without the right satellite airtime plan, your equipment is essentially dormant. Airtime is what connects your device to its network, enabling calls, SMS, data, tracking, and SOS messaging from anywhere on Earth that the relevant satellite constellation covers.

At GTC, we supply airtime for all the major networks: Iridium, Inmarsat, Globalstar, and Garmin, alongside Thuraya and Starlink. This guide focuses on the four most popular constellations, breaking down how each network works, what airtime options are available, and which use cases each is best suited to, so you can make a confident, informed choice.

1. What Is Satellite Airtime and Why Does It Matter?

Satellite airtime is the service plan that grants your device access to a satellite network, analogous to a mobile tariff on a smartphone. Just as a SIM card without a mobile plan cannot make calls, a satellite device without an active airtime subscription cannot transmit or receive data over its satellite constellation.

Airtime plans dictate how many minutes or megabytes you have available, where in the world those allowances are valid (regional vs. global), how long your credits or plan remain active, and what features are included, voice, SMS, data, tracking, and SOS alerts.

Choosing the wrong airtime plan can mean paying for coverage you don't need, running out of credits in a critical moment, or finding your device inactive when it matters most. Getting it right saves money and, in remote environments, can be genuinely life-saving.

2. Prepaid vs. Monthly Contract: Which Is Right for You?

GTC offers two main airtime models across all networks.

Prepaid airtime works like a voucher; you buy a set amount of credit (minutes or data) and use it within a defined validity period. There's no ongoing commitment, making it ideal for occasional travellers, seasonal users, or anyone who wants maximum flexibility. Top-up vouchers let you add credit to an existing prepaid account instantly, online or by phone.

Monthly contract plans charge a regular fee for an included allowance, typically at a lower per-unit rate than prepaid. They're better value for regular users, professional deployments, and anyone who needs guaranteed access month after month. Many plans also include rollover minutes or additional benefits not available on prepaid.

SIM-only plans let you bring your own device and simply add a SIM, ideal if you already own compatible hardware and just need to activate or switch service.

Not sure which suits you? GTC's team can advise on the right balance between flexibility and cost-efficiency based on your usage pattern.

3. Iridium Airtime Plans

True global coverage, the only satellite network that covers every inch of Earth

Iridium operates a constellation of 66 low-earth orbit (LEO) satellites that together provide unbroken, pole-to-pole coverage of the entire planet. This includes the oceans, the Arctic, the Antarctic, and every remote landmass in between. No other commercial satellite network matches this footprint. For anyone venturing truly off-grid, from polar expeditions to transoceanic voyages, Iridium is the network of choice.

Because Iridium's satellites orbit at low altitude (approximately 780 km), latency is lower than geostationary systems, call quality is consistent, and signal acquisition is fast. Iridium is the backbone of many professional and government emergency communication systems worldwide.

Iridium Airtime Options at GTC

GTC stocks a comprehensive range of Iridium airtime to suit satellite phones, the Iridium GO! Wi-Fi hotspot, the Iridium GO! exec, and IoT or tracking devices.

Iridium Sat Phone Top-Ups (Prepaid)
From £53 ex. VAT. Credit applied instantly, ideal for travellers and expedition users who need flexibility without a contract.

Iridium Prepaid SIMs
From £136 ex. VAT. A SIM with an included prepaid credit bundle, perfect for new users activating a satellite phone for the first time.

Iridium Standard Pay Monthly Plans
From $54.95/month. Includes a monthly minute allowance, suited to regular users, corporate deployments, and maritime and field operations.

Iridium GO! Standard Pay Monthly
From $71/month. For groups needing satellite Wi-Fi hotspot connectivity via the Iridium GO! device.

Iridium GO! Top-Ups (Prepaid)
From £57 ex. VAT. For existing GO! device owners topping up credit as needed.

Iridium SIM Card
£8 ex. VAT. A replacement or new SIM with no airtime included, for device owners who need to swap or activate a SIM only.

Key Advantages of Iridium Airtime

Iridium offers genuine global coverage, including both polar regions, open oceans, and all continents, something no other commercial network can claim. Consistent call quality comes from its low-earth orbit architecture, with reduced latency compared to geostationary systems. The network is compatible with a wide range of devices, including the Iridium 9555, 9575 Extreme, Iridium GO!, and GO! exec. Plans are available for voice, SMS, and data depending on device, and span everything from short prepaid bundles to long-term monthly contracts.

GTC Tip: If you travel to polar regions or operate at sea, Iridium is the only network that will keep you connected throughout your journey. Regional networks have coverage gaps in extreme latitudes. For year-round professional use, a monthly contract plan offers significantly better per-minute value than prepaid top-ups.

Who Uses Iridium?

Maritime professionals, offshore oil and gas teams, mountain rescue organisations, polar researchers, military contractors, aid organisations, and expedition travellers. If you need to be contactable, or able to call for help, from any location on Earth, Iridium is the definitive answer.

4. Inmarsat Airtime Plans

Industry-leading broadband at sea and on land, the professional's network

Inmarsat has been at the heart of satellite communications since 1979, operating a fleet of GEO satellites positioned 35,786 km above the equator. This high altitude means a small number of satellites can cover vast portions of the globe simultaneously. Inmarsat's coverage spans approximately 85% of the Earth's surface, excluding the extreme polar regions, which covers virtually all populated areas, shipping lanes, and key remote regions worldwide.

Inmarsat is particularly renowned for its maritime communications, powering connectivity on everything from fishing vessels and superyachts to commercial shipping fleets and naval vessels. The network also supports land-based broadband through its BGAN terminals, widely used by journalists, humanitarian workers, and disaster response teams.

Inmarsat Airtime Options at GTC

IsatPhone Top-Ups (Prepaid)
From £13 ex. VAT. Top up an existing IsatPhone 2 or IsatPhone Pro account instantly.

IsatPhone Prepaid SIMs
From £13 ex. VAT. A SIM with included prepaid credit for new IsatPhone activations.

BGAN Top-Ups (Prepaid)
From £38 ex. VAT. Data credit for BGAN broadband terminals used in land-based deployments.

Inmarsat Pay Monthly Plans
Contact GTC for current pricing. Monthly contract plans covering IsatPhone and BGAN for corporate and maritime use.

Inmarsat SIM Card
£5 ex. VAT. A replacement or new SIM with no included airtime.

Key Advantages of Inmarsat Airtime

Inmarsat carries an exceptional maritime heritage; it has been the go-to network for vessel communications for decades. Its BGAN broadband offering provides genuine high-speed satellite internet for temporary field offices, broadcast uplinks, and data-heavy applications. Coverage reaches approximately 85% of the Earth's surface, and the geostationary architecture delivers stable, high-bandwidth connections. The network is trusted by governments, NGOs, and enterprise organisations for mission-critical communications worldwide.

GTC Tip: Inmarsat airtime is among the most cost-effective satellite phone airtime available, making it an excellent choice for users in Africa, the Middle East, Europe, and Asia. BGAN is the platform of choice for field broadband, ideal for anyone who needs to send large files, stream video, or run a VPN from a remote location without terrestrial infrastructure.

Who Uses Inmarsat?

Commercial shipping companies, offshore energy operators, broadcast journalists in conflict zones, NGOs in the developing world, government agencies, and any professional who needs reliable broadband connectivity where terrestrial networks don't reach. IsatPhone is also popular with travellers to Africa, the Middle East, and remote parts of Asia where GSM coverage is limited.

5. Globalstar Airtime Plans

Affordable satellite connectivity across North America, Europe, and beyond

Globalstar operates a constellation of low-earth orbit satellites providing satellite voice and data services across a broad but regionally focused coverage area. The network is strongest across North America, Europe, Australia, the Middle East, and parts of Africa and South America, making it a cost-competitive option for users who operate primarily within these regions.

Globalstar is perhaps best known to the consumer market as the satellite technology underpinning Apple's Emergency SOS via satellite, a testament to the network's reliability for safety-critical applications. The network also powers the SPOT family of satellite messengers and trackers, among the world's most popular personal safety devices.

Globalstar Airtime Options at GTC

Globalstar Pay Monthly Plans
Competitive monthly rates for regular users within Globalstar's coverage footprint. Contact GTC for current pricing on plans suited to your device and usage.

SmartOne Asset Tracker Airtime (Monthly)
IoT-specific monthly plans for the SmartOne asset tracker, supporting location monitoring and telemetry for fleet and equipment management.

Key Advantages of Globalstar Airtime

Pricing for Globalstar airtime is quite competitive within its covered regions, often with lower per-minute rates than comparable networks. Its LEO architecture delivers lower latency and reliable voice quality. Coverage across North America and Europe is strong and well-established, and the network's safety credentials are reinforced by its role powering Apple's Emergency SOS. Dedicated IoT plans for the SmartOne tracker make it a practical option for asset monitoring deployments.

Coverage Note: Unlike Iridium, Globalstar's coverage does not extend to the polar regions and has some gaps over open oceans. If your operations take you beyond Globalstar's defined coverage zone, Iridium is the safer choice. Within covered regions, however, Globalstar offers excellent value.

Who Uses Globalstar?

Outdoor enthusiasts, agricultural businesses, construction firms tracking equipment, lone workers in rural North America and Europe, and organisations needing cost-effective satellite connectivity within a defined region. The SmartOne tracker is particularly popular for fleet management and remote asset monitoring.

6. Garmin inReach Subscription Plans

Two-way satellite messaging, tracking, and SOS from the brand adventurers trust

Garmin inReach devices are two-way satellite communicators that run on the Iridium network, meaning they benefit from Iridium's unmatched global, pole-to-pole coverage. Unlike a traditional satellite phone, inReach devices are compact, lightweight, and designed specifically for outdoor adventurers, hikers, climbers, kayakers, skiers, and cyclists who need safety connectivity without carrying a full satellite handset.

inReach devices allow users to send and receive SMS messages via satellite, track their route with GPS, share their location with friends and family through the Garmin Explore app, and, critically, trigger a 24/7 GEOS-monitored SOS response from anywhere in the world. The Garmin inReach Mini 2 and inReach Messenger are among the smallest and lightest satellite communicators on the market.

Garmin inReach Subscription Plans at GTC

GTC supplies the full range of Garmin inReach subscription plans, available as flexible monthly rolling subscriptions.

Safety Plan
Designed for users who primarily want emergency capability, with unlimited SOS access, basic location tracking, and a limited message allowance.

Recreation Plan
An increased message allowance and unlimited tracking for weekend adventurers and regular trail users who want to stay in touch during their trips.

Expedition Plan
Higher message bundles, in-reach weather forecasts, and unlimited tracking for multi-day expeditions, professional guides, and remote workers who depend on consistent communication.

Freedom Plan
A flexible plan that can be activated and suspended on a month-by-month basis, ideal for seasonal users such as winter sports enthusiasts or summer trekkers who don't need year-round service.

Key Advantages of Garmin inReach Airtime

Garmin inReach plans sit on the Iridium network, delivering genuine global coverage including Antarctica. Two-way messaging means you can receive replies from contacts via SMS, email, or the Garmin Explore app, not just send one-way alerts. The monitored SOS links directly to the GEOS International Emergency Response Centre, which coordinates rescues 24 hours a day, seven days a week. Weather forecasts are available via satellite on higher-tier plans, adding meaningful safety value for mountaineers and sailors. Route tracking lets family members and rescue services follow your progress in real time.

GTC Tip: For adventurers who don't need full satellite phone capability, a Garmin inReach paired with a Recreation or Expedition plan is one of the best-value safety investments available. The Freedom Plan's ability to be suspended and reactivated monthly means you only pay for the months you're actively out there, a significant saving compared to a fixed 12-month contract.

Who Uses Garmin inReach?

Hikers, mountaineers, trail runners, kayakers, cyclists, hunters, skiers, backcountry snowboarders, sailors, and any individual who ventures into areas without mobile coverage. It's also popular with families as a way of staying informed about a loved one's whereabouts during remote trips, and with professional guides who carry it as a standard safety tool alongside their clients.

7. Side-by-Side Network Comparison

Feature	Iridium	Inmarsat	Globalstar	Garmin inReach
Satellite Type	LEO (66 sats)	GEO (3 sats)	LEO (24 sats)	LEO (Iridium network)
Polar Coverage	Yes	No	No	Yes
Open Ocean Coverage	Full	Full	Partial	Full
Voice Calls	Yes	Yes	Yes	No (text only)
Two-Way SMS	Yes	Yes	Limited	Yes
Data / Broadband	Limited	Yes (BGAN)	Limited	No
GPS Tracking	Via apps	Via apps	SmartOne device	Built-in
SOS / Emergency	Yes	Yes	Yes	Yes, 24/7 GEOS
Prepaid Options	Yes	Yes	Monthly only	Yes, Freedom Plan
Best For	Global & polar use	Maritime & broadband	N. America & Europe	Outdoor adventure

 

8. How to Choose the Right Satellite Airtime Plan

With so many options across four major networks, the right choice comes down to answering a few key questions about your situation.

Where are you going? If you'll be in polar regions or over open ocean, only Iridium covers you fully. For most populated areas and key remote regions, all four networks perform well.

How often will you use it? Occasional users benefit from prepaid flexibility. Regular users and professionals get meaningfully better value from monthly contracts.

What do you need to do? Voice calls, SMS, broadband data, GPS tracking, and SOS monitoring are not all available on every network. Match your requirements to the right service before you commit.

What device do you already own? Your device dictates which network you're on. If you're buying new, GTC can help you choose the right device and airtime combination from the start.

What's your budget? Prepaid plans start from as little as £13 ex. VAT for Inmarsat IsatPhone credit, making satellite connectivity more accessible than many people expect.

Still unsure? GTC's expert team is available on 0800 112 3919 (UK freephone) or +44 1202 801290 (international) to talk through your requirements and recommend the most appropriate airtime solution for your specific situation. You can also browse our full range of satellite airtime plans, prepaid top-ups, SIM cards, and monthly contracts, at gtc.co.uk/collections/airtime.