Why Is My Data Slow?

You're connected, you have bars, but pages crawl and video buffers. "Slow data" is one of the most common things travellers report, and it's almost always one of a small handful of causes — most of them not actually problems with the plan.

Cause 1 — Weak signal

The number of bars tells you how strong the connection is, not how fast it is. But weak signal directly throttles speed.

Things that hurt signal:

• Inside buildings, especially concrete / steel / underground (basements, metros, large hotels).
• Far from the nearest cell tower (rural areas, mountains, small islands).
• Bad weather — heavy rain and storms degrade signal.

Try moving location: walk outside, towards a window, away from thick walls. If the speed jumps, signal was the problem.

Cause 2 — Congestion

Mobile networks have finite bandwidth per tower. When thousands of phones share one tower at the same time, everyone gets slower. This is by far the most common reason travel eSIMs feel slow.

Hot spots:

• Tourist attractions during peak hours. A famous square at sunset. A beach during the day. Festival crowds.
• Airports during boarding/arrival rushes.
• Major events — concerts, sports matches, parades.
• Evenings in dense city centres when locals are out + on their phones.

Try the same speed test at the same spot 2 hours later — if it's faster, congestion was the cause.

Cause 3 — 5G with weak coverage

5G is faster than 4G only when the signal is strong. With a weak 5G signal, your phone clings to a worse connection that a strong 4G would beat.

Forcing 4G is a known trick that often improves real-world speed when 5G coverage is patchy:

• iPhone: Settings → Cellular → tap the esimple plan → Voice & Data → pick LTE.
• Android: Settings → Network & internet → SIMs → tap esimple → Preferred network type → LTE/4G.

Try this if your phone shows 5G but speeds feel awful.

Cause 4 — The local network the SIM is using

esimple plans often have access to multiple networks in a country. Sometimes the network your phone picks first isn't the best one available — usually because the phone latched on at the airport and never re-evaluated.

Try a manual network reset:

• iPhone: Settings → Cellular → tap the esimple plan → Network Selection → turn Automatic off, wait 20 seconds, turn it back on. The phone will rescan and often pick a better network.
• Android: SIM settings → Mobile network → Network operators → Search → pick the strongest local network manually, then switch back to Automatic.

Cause 5 — VPN

VPNs add a hop and an encryption layer. Speed always takes a hit. If you're behind a corporate VPN or a personal one and things feel slow, try briefly disabling it and see if speed jumps.

When "slow" is normal

• Slower than home wifi. Always. Mobile data is rarely as fast as good wifi.
• Speed varying day to day. Networks fluctuate. A speed test at 7 AM and 7 PM at the same location can be 10x different.
• First few minutes after connecting in a new country. The phone settles in. Speed often improves once it's been on the network for an hour.

When to actually worry

• Less than 1 Mbps consistently, day after day, in multiple locations.
• Speed fine for a day then drops sharply with no obvious cause.
• Specific apps blocked (this is sometimes a country-level issue — see Country-specific issues).

If any of those apply, email support@esimple.ai with:

• The country and city.
• A screenshot of a speed test result (use fast.com or speedtest.net).
• The time of day.
• Your phone model.

We can check whether the eSIM is on the optimal local network on our side, and switch it manually if needed.