Since Starlink Maritime arrived, the assumption in Singapore has been that Iridium is on its way out for anything except emergency backup. That’s mostly true — but not entirely. Iridium Certus (the modern Iridium broadband service) still wins in specific vessel scenarios where Starlink either can’t legally operate or can’t provide the certified voice services required. This post covers when each is right and when to run both.
Iridium Certus in one paragraph
Iridium Certus is the broadband service from Iridium’s second-generation NEXT constellation of 66 LEO satellites. Global pole-to-pole coverage. Two speed tiers — Certus 200 (176 kbps) and Certus 700 (704 kbps). Voice + text + data over one antenna. Very low bandwidth by Starlink standards (Starlink is 100-300x faster), but with global coverage, certified safety voice, and rock-solid reliability.
Side-by-side comparison
| Attribute | Iridium Certus 700 | Starlink Maritime |
|---|---|---|
| Peak throughput | 704 kbps down / 352 kbps up | 50-220 Mbps down / 15-30 Mbps up |
| Latency | 60-120 ms | 40-80 ms |
| Coverage | Truly global including polar | Global maritime + regional; some restricted zones |
| Hardware (SGD) | 10,000-15,000 | 4,500-5,500 |
| Monthly airtime (SGD) | 500-1,500 depending on usage | 320-1,050 |
| Voice | Yes — certified GMDSS voice | Data-only (VoIP works but not certified) |
| Antenna size | Small (30-40 cm dome or flat) | Medium (60 cm flat) |
| Best for | Backup, polar work, GMDSS voice | Primary broadband, crew, ops |
Scenarios where you still need Iridium Certus
1. Polar operations — Iridium’s pole-to-pole coverage is genuine. Starlink polar coverage exists but is thin and unreliable above 70°N/S. Vessels operating in Arctic or Antarctic waters must have Iridium.
2. Certified GMDSS voice — since IMO recognised Iridium as a GMDSS provider (2020), Iridium Certus voice can substitute for Inmarsat C in the distress alerting chain. Starlink Maritime does not have GMDSS status.
3. Starlink-restricted waters — a growing list of national waters where Starlink Maritime cannot operate (some Chinese, Iranian, Russian EEZs, some parts of India, some African). Iridium works everywhere.
4. Deep-hull vessels with limited antenna line-of-sight — Iridium antennas are much more forgiving of obstruction than Starlink flat panels. Some submarine-support vessels and specialised platforms rely on this.
5. Emergency-only backup on a Starlink-primary fleet — Iridium Certus 200 at basic airtime (~SGD 200/month) is cheap insurance against any single-provider outage.
Where Starlink Maritime wins outright
- SE Asia commercial waters (SG, MY, ID, VN, PH, TH, MMR)
- Bandwidth-hungry applications: crew welfare, video, cloud sync, remote support
- Cost per megabit (Starlink is ~200-500x cheaper per byte)
- Speed of deployment (Starlink kit from Singapore stock, install in one afternoon; Iridium Certus 6-12 week lead time)
Not sure which satellite phone or airtime plan fits your crew?
Tell us where you operate and how often you call. We will recommend a handset and a plan that does not waste money.
The bonded design — Iridium as safety backup behind Starlink
For Singapore commercial vessels that need certified GMDSS voice plus commercial-grade broadband, the modern setup is:
- Primary broadband: Starlink Maritime + OneWeb bonded on Peplink B One
- Certified GMDSS voice: Iridium Certus 200 or Iridium GMDSS handset
- Emergency backup: IsatPhone 2 handheld
Total hardware SGD ~15,000-20,000 per vessel. Monthly airtime SGD ~1,700-2,200 combined. Payback against traditional VSAT + Inmarsat FBB in under 12 months.
Why Iridium Certus is unlikely to disappear
Certus is a low-bandwidth, high-reliability, low-latency safety service. Starlink is a high-bandwidth, high-reliability, low-latency commercial service. These are different products, not competitors. Iridium’s IMO GMDSS approval and polar coverage make it a permanent fixture in maritime comms. What has changed is that Iridium is no longer the primary broadband — it’s the safety backbone.
Related reading
- Iridium GMDSS vs Inmarsat GMDSS
- Iridium 9555 vs IsatPhone 2
- Bonded Starlink + OneWeb + Peplink guide
Get an Iridium Certus quote
Tell us the vessel type and coverage requirements — we will quote Iridium Certus 200 or 700 with hardware, install, and airtime. Singapore stock for Certus 200 handhelds; Certus 700 terminal on order. Sales at Envisiondata Pte Ltd — sales@envisiondatasg.com — or WhatsApp Steve directly on +65 9088 4899.
How we can help
Satellite voice is simple to buy and easy to overpay for. We match handsets and airtime to how your vessels actually operate.
- Free handset and airtime recommendation
- Prepaid and postpaid plans in SGD
- Spare batteries, docks and antennas
- Activation and support from Singapore
What happens when you contact us
- Short call or meeting — we listen to how your vessels operate.
- Vessel and route review — we check equipment, space, power, contracts and licensing.
- Clear recommendation — a written proposal and SGD quote, with options.
- Install and support — commissioning, testing and ongoing support.
Related: Why fleets now pair Starlink with OneWeb
Get a free satellite phone recommendation
There is no obligation. If your current set-up is already the right one, we will tell you.
About the author
Steve leads Envisiondata Pte Ltd in Singapore. He has more than 20 years in cables, telecom infrastructure and satellite communications across ASEAN. He designs and supports connectivity for tugs, OSVs, harbour craft and commercial fleets across the region.
Written by Steve
Steve has over 20 years of experience in cables, telecom infrastructure and satellite communications across ASEAN. He founded Envision Data to help Singapore and SE Asia vessel operators choose and run the right maritime connectivity, from Starlink and OneWeb to Iridium, Inmarsat and GMDSS.
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