Swiss mobile roaming experience significantly differs from the domestic one

In this new analysis, Opensignal has compared the roaming experience of our smartphone users on Switzerland’s mobile networks — Salt, Sunrise, and Swisscom, over the course of 180 days starting on October 1, 2022. We looked at the quality of roaming services seen by our Swiss users traveling abroad to neighboring countries — Austria, France, Germany, and Italy. We also analyzed the experience of roamers from these markets when they use their phones on Switzerland’s networks — and how it compares to the experience of Swiss domestic users.

Opensignal data shows that our Salt users enjoy the fastest 4G and 5G download speeds and the best Excellent Consistent Quality when roaming outside Switzerland in nearby countries.

Our users from Austria, France, Germany, and Italy generally see a worse experience on Swiss networks compared to Swiss users’ domestic experience. Users who roam on Sunrise’s network see the biggest discrepancy for 5G Download Speed and Excellent Consistent Quality.

Salt users enjoy the fastest average 4G and 5G download speeds when connecting to mobile networks outside of Switzerland — in Austria, France, Germany, and Italy. Salt users have an average 4G download speed of 46.1Mbps and Salt commands a solid lead over its Swiss competitors — around 4.3Mbps (10.2%) faster than Swisscom users and 10.7Mbps (30%) faster than Sunrise users. Our Salt users also see the fastest 5G download speeds when roaming in neighboring countries, clocking in at 193.8 Mbps — 41.7-58.9% faster than their Sunrise and Swisscom counterparts, as both operators are in a statistical tie.

Looking at upload speeds, Salt and Swisscom are statistically tied for 4G Upload Speed, with scores of 9.4-10.6Mbps. However, for 5G Upload Speed, Salt is tied with Sunrise, with scores of 17.4-22.4Mbps.

At first glance, Swisscom users lagging behind Salt on 5G speed may be surprising because in the recent Opensignal Switzerland report Swisscom won all four speed awards outright. However, the roaming mobile network experience does not depend on an operator’s home network infrastructure but relies more on which roaming partners they selected to provide services to their customers abroad.

Looking at Swiss users’ experience in neighboring countries they visit, the fastest average 4G Download Speed is in Germany clocking in at 43.7Mbps. However, Swiss roamers in Germany also observe the slowest 5G download speeds which are around 40.9Mbps slower than when they visit France or Italy.

Opensignal also analyzed how consistent the mobile experience of our Swiss users is when they connect to mobile services abroad. To do so, we looked at Excellent Consistent Quality, which quantifies how often users’ experience on a network is sufficient to support more data-demanding applications’ requirements. The measurements include download speed, upload speed, latency, jitter, packet loss, time to first byte, and the percentage of tests attempted which did not succeed due to a connectivity issue on either the download or server response component. Latency is likely to be affected by international roaming given additional steps mobile connections need to follow, like reaching back to the operator’s home network.

Looking at the Excellent Consistent Quality scores of Swiss operators when their users roamed in Austria, France, Germany, and Italy — Salt has the highest score, meaning it meets the minimum recommended performance thresholds for HD video, group video conference calls, and gaming in 77.9% of users’ tests. It beats statistically tied Sunrise and Swisscom by around 4.6 percentage points.

Opensignal also analyzed the aggregated experience of our users from Austria, France, Germany, and Italy, when they connect to mobile services in Switzerland. This time, international roamers’ experience is more aligned with the experience of Swiss users on their domestic networks. Our users from four of Switzerland’s neighbors see the fastest 4G Download Speed and 5G Download Speed on Swisscom’s network, clocking in at 56.1Mbps and 221.4Mbps, respectively.

Austrian, French, German, and Italian users who travel to Switzerland, together on average see slower 4G and 5G download speeds than our Swiss users on the same mobile networks. International roamers observe 4G download speeds that are 14.7% slower on Salt, 13% slower on Sunrise, and 10.3% slower on Swisscom, than what the domestic users enjoy. The relative differences are higher for 5G Download Speed for Salt — 16.9% — and much higher for Sunrise, where international roamers see 38.3% slower 5G download speeds than the domestic users of this network. International roamers’ experience on Swisscom’s network is not statistically different from what its domestic users see.

We looked at the roaming experience of French, German, and Italian users coming to Switzerland as well. While French and Italian users see statistically similar average 4G download speeds when roaming on Swiss networks (51.1-51.2Mbps), their German counterparts’ experience is around 7.6Mbps slower. Meanwhile, our users with German SIM cards hosted by Swiss networks also observed much slower 5G Download Speed than their French and Italian peers.

Comparing the consistency experience of Austrian, French, German, and Italian visitors to Switzerland to one of the Swiss domestic users, we observed significantly lower Excellent Consistent Quality scores across all Swiss operators. The difference ranges from four and 7.4 percentage points for Salt and Swisscom, respectively, to a wider 14.9 percentage points for Sunrise. Roamers’ experience with Salt and Swisscom is statistically similar.

Overall, our Swiss users spend between 27.7% to 33.6% of their time on Wi-Fi when roaming. Our Swiss users spend a lot less time on Wi-Fi when roaming compared to their domestic use — the difference is especially wide in the case of Sunrise and Swisscom. While users on both of these networks spend around 50% of their time on Wi-Fi in their home Switzerland, these numbers drop significantly abroad in Austria, France, Germany, and Italy, by 23.6 percentage points for Swisscom and 16.1 percentage points for Sunrise. Salt users also spend less time on Wi-Fi when abroad than at home, by 5.8 percentage points.

Users connecting to their home or work Wi-Fi on their mobile devices would explain the significantly higher scores for Time on Wi-Fi in Switzerland than in roaming. This also shows that Swiss mobile users are comfortable with using their mobile plans, as opposed to relying heavily on Wi-Fi to help reduce mobile roaming costs.

When looking at the Time on Wi-Fi that our users from France, Germany, and Italy spend across different Swiss operators, we observed substantial differences between these groups. Time on Wi-Fi ranged from 16.6% for French users through 26.5% for Italian users to more than half of the time for German users. Users from these countries connect to Wi-Fi for less amount of time than at home — while in Germany and Italy, the drops are 8.7 and 7.1 percentage points respectively, we observe a much higher drop in the case of French users, who spend less than half of the time on Wi-Fi in Switzerland than they do at home — a drop of 25 percentage points. These differences can be explained by destinations that international roamers visit, like Swiss ski resorts — where they are likely to spend a lot of time outdoors — but also by their own smartphone use habits at home, whether they rely heavily on Wi-Fi.

The mobile roaming experience is essential for frequently traveling users. As our analysis shows, it can differ substantially from the domestic experience that mobile users are used to — and with attractive mobile plans, users are likely to rely less on hunting for Wi-Fi hotspots when traveling abroad. While the development of eSIM is likely to shake up the way smartphone users can access mobile services abroad, operators are forming international partnerships to develop such roaming solutions as low-latency data roaming or intercontinental 5G Standalone connections.