WLAN-Telefonie im Ausland: Vergleichen Sie alle US-Karten | MollySIM

A local network name on your phone does not establish that your US plan allowance works abroad. With Lyca Mobile US, your SIM can register on a local tower while its allowance still requires Wi-Fi Calling. With T-Mobile, only the $15/mo plan has cellular roaming; the other plans need Wi-Fi Calling for US voice and SMS abroad. Choose your card by the service you need to use, then test that service before departure.

What T-Mobile Wi-Fi Calling and Lyca do abroad

For the T-Mobile plans without roaming, Wi-Fi Calling lets you use your US line over Wi-Fi outside the US. You can call US numbers, receive calls from US numbers, and receive US SMS, including bank codes. The US-number restriction matters when you need to contact someone at your destination.

Lyca's rule covers its plan allowance: outside the US, data, calls and SMS require Wi-Fi Calling switched on. Registration on a local cellular network does not remove that requirement. Do not interpret the listed US data allowance as an overseas cellular data package.

Every card here has a native US number and is activated for you before shipping. T-Mobile cards are also bound to your number.

Card-by-card: registration, allowance and US voice/SMS abroad

Prices are MollySIM retail prices in USD, separate from the plan names. Lyca allowances cover 30 days.

For the T-Mobile plans without roaming, the confirmed overseas SMS use is receiving US messages. Do not expand that into an unsupported promise about outbound SMS abroad. Likewise, do not read missing details in the $15/mo row as either an inclusion or an exclusion.

Turn it on in 5 steps

Follow the options your handset presents; menu paths and compatibility are not specified here.

1. Identify your US line. Confirm which installed SIM is your MollySIM number. On iPhone, work with that line's settings; on Android, select that SIM wherever the phone offers a SIM choice.
2. Find and enable Wi-Fi Calling. Search Settings for “Wi-Fi Calling” and enable it for your US line if the option is available. On either platform, stop and investigate a missing toggle rather than assuming activation has enabled the feature.
3. Complete any E911 address prompt. If setup requests an emergency address, follow the displayed requirements and provide accurate information. Resolve an incomplete address prompt before testing.
4. Check the voice and default-SMS line. Select your US line for the test call. On Android, check any default-SMS SIM selector; on iPhone, check the line selected for any test message you compose. For incoming codes, verify the number saved with the sender.
5. Turn roaming OFF for this check and join Wi-Fi. Disable the US line's roaming option where available, then connect to Wi-Fi. Keep the $15/mo T-Mobile China roaming benefit separate from this Wi-Fi Calling check. A roaming setting alone is not proof that a call used Wi-Fi Calling.

Test before you leave the US

Use your travel phone and US line. Look for confirmation that Wi-Fi Calling is active; merely joining Wi-Fi does not verify your calling setup.

Call a US number, arrange an incoming call from a US number, and request an SMS to your US number. Include a code from the service you intend to access abroad. Record which checks passed, including the sender of the code, rather than treating a successful call as proof that every message will arrive.

If you cannot confirm the connection used, treat the result as inconclusive. A successful cellular call in the US does not test the overseas Wi-Fi Calling requirement. Resolve missing settings or failed tests before departure, and repeat the relevant checks after you arrive.

Wi-Fi Calling not working abroad: troubleshooting

Test each change separately so you can identify what affected the result.

If something appears wrong with the card, give MollySIM support the plan, handset, destination and failed checks. Support reviews card problems individually; no particular outcome is promised.

What Wi-Fi Calling cannot do

For T-Mobile's non-roaming cards abroad, US numbers only is the rule. Wi-Fi Calling does not make those plans a substitute for calls to local hotels, restaurants or drivers. Plan separately for those calls.

Lyca's $15 plan lists international calls to 80+ destinations, but that is not a blanket promise of local calling while travelling. Lyca's published terms limit “unlimited international calls” to the first 10 dialled numbers per country, excluding Morocco IAM/Wana and Israel prefixes 97256/97259. Confirm your intended use rather than extending that allowance by assumption.

Wi-Fi Calling also does not turn Lyca's US data into a stated overseas cellular allowance. T-Mobile's specified roaming data benefit here belongs to the $15/mo plan: 1GB in China.

Choosing T-Mobile $10/$15 or Lyca

Choose the T-Mobile North America SIM $10/mo option if unlimited US calls and SMS suit your needs and you can meet its overseas Wi-Fi Calling requirement. Its retail price is $23.99. Choose the $15/mo option, at $25.00, for the stated 1GB China roaming and free incoming benefit; do not infer an unlimited overseas voice/SMS package.

For Lyca Mobile US, compare the $10 plan's 300MB US data and 3,000 min + 3,000 SMS with the $15 plan's 1GB US data and unlimited US talk/SMS. Their retail prices are $29.99 and $34.99 respectively. Both require Wi-Fi Calling for the allowance abroad.

FAQ

Can I receive US bank codes abroad?

The T-Mobile plans without roaming can receive US SMS through Wi-Fi Calling, including bank codes. Test your intended sender before travel; do not treat that capability as a guarantee from every bank.

Does Lyca lose its number when the plan expires?

Plan expiry alone does not cancel the number, and a top-up restores service. Lyca's published terms state that the SIM and assigned number expire after 60 consecutive days of non-use.

Can I order these cards as an eSIM?

Every physical card can also be delivered as an eSIM. Write eSIM in your order note to receive the activation QR code by email.

Does an activated card finish my phone setup?

No. All cards are activated for you before shipping, but you still need to configure and test Wi-Fi Calling on your phone.

Can I return an activated card if I change my mind?

Activated cards have no change-of-mind refunds. A non-faulty Lyca card is not refundable once sold. If something is wrong with your card, support reviews it individually.

For your next checks, read using a US number for bank verification and data-only versus voice/SMS plans.