Do you really need 5G roaming data for your Southeast Asia holidays? Opensignal has answers

Ever wondered if the 5G or 4G roaming data you buy for your holidays are worth the money spent? Now, there’s some data available from Opensignal to help us understand our mobile network coverage a little better.

In a whitepaper about ASEAN network infrastructure published by Opensignal, the network analytics firm published various mobile connectivity results across Southeast Asian countries (Singapore, Malaysia, Thailand, the Philippines, Brunei, Vietnam, Laos, Indonesia, Cambodia, and Myanmar). 

While the whitepaper discussed how our region still has room to grow its connectivity prowess, the information helps travellers to the region (and its locals) understand whether it’s worth buying a fast roaming data plan when they come over. 

It’s not explicitly mentioned that this study caters to roaming data plans, but you’re pretty much at the mercy of the local network infrastructure and coverage when you’re in town.

The whitepaper examines several key details, including the time mobile devices spend connected to 5G, 4G, 3G, and 2G mobile networks, as well as which countries are utilising the 3.5GHz spectrum for 5G networks. While it’s all really dry to read, the infographics are helpful in helping travellers to Southeast Asia understand if they really need a 5G or 4G roaming data mobile plan.

Note that the information and data collected by Opensignal was taken between 1 May and 29 July 2025.

23% of the time, every time

First things first: Phones in Singapore spend only 23% of their connected time on a 5G network, and it’s actually the highest duration out of all the SEA countries that Opensignal checked. Second is Malaysia (16%), and some SEA neighbours don’t even carry 5G networks at all (Cambodia, Myanmar).

From the analysis, it’s clear that obtaining a 5G roaming data plan highly depends on the country in the SEA region you’re visiting. Singapore, Malaysia, and Thailand are much more likely candidates for your roaming data plan to connect to their respective 5G networks.

It’s possible that the 1% 5G duration for Vietnam, Laos, and Indonesia refers to a very small area of 5G network coverage or lower 5G phone adoption among the local population. The good news is that most ASEAN countries can support a 5G mobile plan, roaming or not.

Notably, you should not expect 3G network coverage if you’re moving around SEA. Phones spend less than 10% of their time on a 3G network in the surveyed countries, and that’s likely because most of them have already switched off 3G connectivity as of 2022 or 2023.

More 3.5GHz, more better?

Secondly, it is Malaysia (99%) – not Singapore (76%) – that has the most consistent distribution of 3.5GHz spectrum for 5G networks in Southeast Asia. While this is less helpful for tourists and consumers, it remains an important indicator for phone brands to determine the types of 5G network bands supported in our region, especially if they wish to sell more phones to our friends and neighbours in SEA.

In a nutshell, you’d definitely want a phone that can handle 3,500MHz, 2,600MHz, and 1,800MHz bands for 5G connectivity, with support for the 700MHz band if you want the phones to connect well in Brunei. For travellers, this matters if you’re checking whether your roaming telco provider can handle a 5G connection to your phone.

Is the 5G network really faster, or is it just for show?

Finally, Opensignal found that 5G connectivity does have the tangible benefit of faster download speeds. The graph is somewhat bare, but it indicates that a phone on 5G networks in Malaysia is 6.3 times faster than one on 4G in the same country. For Singapore, a 5G-connected phone can be up to 5.8 times faster than one that’s limited to a 4G network. 

From the way the graph is presented, it appears that getting 5G roaming data is most visibly valuable if the place you’re visiting has faster downloads (Singapore, Malaysia, Thailand, and the Philippines), given the bigger 5G vs 4G speed differences in these places.