Data Roaming & IDD Guide: What Is It & How to Activate

Staying connected overseas is essential—whether you’re navigating a new city, receiving banking OTPs, coordinating travel plans, or working on the go. Data roaming ensures your phone remains online the moment you land, without needing to buy local SIMs or rely on airport Wi-Fi.

This guide explains what data roaming is, how it works, APAC and SEA roaming differences, how to activate roaming, and why StarHub’s 5G Unlimited+ Plans offer a more reliable and worry-free way to stay connected while travelling.

✈️ What is Data Roaming?

Data roaming is a service that allows your smartphone to connect to the internet, send messages, and make calls when you are outside your home network's coverage. Essentially, roaming data refers to the mobile internet you use while traveling internationally by "piggybacking" on a local carrier's towers.

When your phone can no longer detect a StarHub signal (e.g., after landing in Tokyo or London), it automatically finds a local partner network. Once connected, you can browse, use maps, and run apps exactly as you would in Singapore.

💡 Why is it called "Roaming"?

The term comes from the concept of your device "wandering" off its home turf. While you are physically in another country, your digital identity (your phone number and SIM profile) remains anchored to Singapore. This allows you to:

• Keep your Singapore number active for urgent calls.

• Receive One-Time Passwords (OTPs) for banking and apps.

• Avoid swapping SIM cards or carrying a second phone.

   

🌐 How Data Roaming Works

For travelers, the experience is seamless, but here is how data roaming works behind the scenes:

🌏 What is APAC Roaming?

APAC roaming is regional mobile data coverage across Asia-Pacific countries. Instead of paying separate rates for each destination, APAC roaming gives you a single data allowance that works across 20 popular travel spots.

Think of APAC roaming as a "multi-country data pass" for the Asia-Pacific region.

Rather than:

❌ Buying a new local SIM in each country

❌ Paying per-megabyte charges that vary by location

❌ Dealing with different activation processes

You get:

✅ One data allowance that works seamlessly across 20 destinations

✅ Predictable costs with no surprise charges

✅ Automatic connection when you land

View the complete list of global destinations covered by our 5G Unlimited+ Plans on our official roaming page.

Why APAC Roaming Is Essential for Singapore Travellers?

Singapore's proximity to popular APAC destinations makes this coverage particularly valuable:

• 🇯🇵 Japan (3.5hr flight) - Tokyo, Osaka, Kyoto
• 🇰🇷 South Korea (6hr flight) - Seoul, Busan
• 🇦🇺 Australia (7-8hr flight) - Sydney, Melbourne
• 🇭🇰 Hong Kong (4hr flight)
• 🇹🇼 Taiwan (4.5hr flight)
• 🇹🇭 Thailand (2.5hr flight) - Bangkok, Phuket

🚀 How StarHub Eliminates Bill Shock

Historically, overseas roaming was billed on a pay-as-you-use basis and charges piled up while you were away and landed on your statement after you got home. Today, StarHub's data roaming on our new 5G Unlimited+ Plans work differently: roaming is a pay-upfront entitlement bundled straight into your monthly subscription.

That means the data, calls, and SMS you use abroad are already paid for. No fluctuating per-megabyte rates, no activation hoops, and no need to buy a separate travel data pack before you fly.

✈️ Seamless Continuity from Take-Off to Landing

No QR codes, no manual setup. Just enable data roaming on your phone and you're connected the moment you land.

📱 Keep your SG Number

Stay reachable on your primary number for OTPs, banking alerts, and important calls while traveling.

📞 Unlimited Calls & SMS

Your connection is active the moment you land, leveraging our premium global partner networks. Even our most affordable 5G Lite Plan comes with unlimited roaming calls & SMS built-in.

➕ Affordable Roaming Data Add-ons Anytime

Need more roaming data? Simply purchase add-on packs via the StarHub app.

• 5GB SEA ($5)
• 10GB APAC ($10)
• 15GB Global ($15)

Plan Comparison: Which One Fits Your Travel Style?

How Your Roaming Data is Consumed

Our roaming plans use intelligent prioritization to keep your costs down. When you travel, your data is automatically deducted in a specific sequence to protect your most versatile data for as long as possible:

1. SEA Data: Used first if you are in one of the 5 Southeast Asian countries.

2. APAC Data: Used next (for Plus Plan users) if you are in Asia-Pacific.

3. Global Data: Only used once your regional allowance is fully utilised, or if you are traveling outside of APAC (e.g., in Europe or the USA).

    

💡 Example:
You're on 5G Unlimited+ Plus with 10GB APAC + 5GB Global. In Thailand, your SEA data depletes first. Then APAC. Global data is saved for Europe/Americas, or as backup.

🌍 How to Activate Data Roaming?

Even with a built-in allowance, your phone’s roaming setting acts as the "master switch". If it remains off, your device will not connect to our global partner networks.

Before You Start: Pre-Activation Checklist

Before traveling, ensure your phone settings are configured correctly:

✅ APN is set to SHWAP

✅ Network selection is set to Automatic

✅ VoLTE is turned on

✅ International Roaming is enabled on your phone

✅ If you have Dual SIM, ensure the correct SIM card is used for data roaming

✅ If you used an eSIM in the past, ensure it is disabled

✅ Restart your phone after changing any settings

Note: Your roaming service is activated automatically with 5G Unlimited+ plans. No manual activation needed.

🍎 Step-by-Step: How to Activate Data Roaming on iPhone

Apple makes it easy to toggle roaming settings. Follow these steps when you arrive at your destination:

🤖 How to Activate Data Roaming on Android?

For Samsung, Pixel, and other Android devices, the steps are similar but the menu names may vary slightly:

After Activation: How to Verify It's Working?

Once you've landed at your destination:

1. Turn off Airplane Mode
2. Wait 30-60 seconds for network search
3. Check status bar for carrier name (e.g., "Softbank" in Japan, "Telstra" in Australia)
4. Open Safari or browser to test internet connection
5. If you see "R" or "Roaming" icon → you're connected ✅

How to Turn Off Data Roaming?

To turn off data roaming, simply reverse the activation steps:

🍎 iPhone: Settings → Cellular → Data Roaming → OFF

🤖 Android: Settings → Connections → Mobile Networks → Data Roaming → OFF

When to turn roaming off:

✅ After returning to Singapore: Prevents accidental foreign network connections

✅ When using Wi-Fi only: If you want to preserve your roaming data and only use Wi-Fi

✅ Border areas: Near Malaysia's border, phones sometimes connect to foreign networks even in Singapore

📞What is IDD (International Direct Dialing)?

IDD stands for International Direct Dialing - the service that lets you call overseas numbers while you're still physically in Singapore.

This is different from roaming calls. With IDD, you are in Singapore calling outbound to another country.

Examples of IDD calls:

📞 Calling a hotel in Bali from Singapore to confirm booking

📞 Phoning a business partner in London from your Singapore office

🤔 How IDD Calls Work?

To make an IDD call from Singapore, you dial:

IDD Prefix + Country Code + Phone Number

Example 1: Calling Jakarta

001 + 62 + 21-1234-5678

• 001 = IDD prefix
• 62 = Indonesia country code
• 21 = Jakarta area code
• 1234-5678 = Local number

Example 2: Calling New York

001 + 1 + 212-555-1234

• 001 = IDD prefix
• 1 = USA country code
• 212 = New York area code
• 555-1234 = Local number

Example 3: Calling London

001 + 44 + 20-7946-0958

• 001 = IDD prefix
• 44 = UK country code
• 20 = London area code
• 7946-0958 = Local number

⏱️ What are IDD Minutes?

IDD minutes are the measurement unit for international calls made FROM Singapore. Some mobile plans include bundled IDD minutes to popular countries, so these calls are already covered in your monthly subscription without per-minute charges.

Think of IDD minutes as your "free international calling credit" - once they're used up, additional IDD calls are charged at standard rates.

🆚 Difference Between IDD and Roaming

IDD = You're IN Singapore calling OUT.
Roaming = You're OUTSIDE Singapore making/receiving calls.

With StarHub 5G Unlimited+, both are included in your plan.

💚 Ready to Travel Worry-free?

Staying connected overseas no longer requires jumping through hoops. By understanding what data roaming is and how to manage it, you can move across borders with the confidence that your maps, banking apps, and messages will work the moment you land.

The days of hunting for physical SIM cards at 3:00 AM in a foreign airport or coming home to unexpected "bill shock" are officially over.

With StarHub 5G Unlimited+, roaming is not an add-on. It is a built-in part of your mobile experience. Whether you are flying to Kuala Lumpur for the weekend or embarking on a month-long road trip across Europe, you have the data you need, on one of Singapore's most reliable 5G networks.

Disclaimer:
This content is provided for general information and convenience. While we take care in preparing our articles, readers should refer to official sources or professional advice for specific, up-to-date details.

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