You receive a Doro phone, take the SIM card out of your old mobile, and it doesn’t fit in the tray. Or worse: it fits, but the phone no longer receives calls a few months later. The physical format of the card is only part of the problem.
With the gradual shutdown of 2G in France, choosing a SIM card for a Doro phone also involves network compatibility, the type of plan, and sometimes even replacing the phone itself.
Shutdown of 2G and Doro phones: the invisible trap before choosing the SIM
Before even discussing nano or micro formats, we need to check a point that most guides overlook: is the Doro phone still compatible with active networks? Arcep reports that the number of devices compatible only with 2G was rapidly decreasing by mid-2026, but a significant number of devices remained in circulation in mainland France.
If the Doro in question only supports 2G (which is the case for several older flip models), inserting a new SIM will change nothing. Traditional voice calls still transit through 2G or 3G on many plans. Once these networks are shut down, only a 4G-compatible phone with VoLTE (voice over 4G network) will allow making and receiving calls.
The concrete step: turn over the phone, note the exact model reference, and then check the technical sheet to see if 4G and VoLTE are mentioned. On a Doro 6060 or a similar model limited to 2G, changing the SIM does not resolve the network incompatibility. The right choice sometimes starts with changing the device.
When looking to choose a SIM card for Doro, this network verification should be the very first reflex, before comparing plans or card formats.
SIM card format according to the Doro model: nano, micro, or standard
Once network compatibility is confirmed, we move on to the physical format. Not all Doro phones use the same SIM size, and getting it wrong means having to request an exchange from the operator or using an adapter (a common source of blockage in the SIM tray).
Identifying the correct format without opening the phone
The quick start guide included with each Doro indicates the required format. On recent Doro smartphones like the Doro 8100, a nano SIM is required. Older flip models, such as the Doro 7080, generally accept a micro SIM.
If the paper guide has disappeared, the product sheet on doro.com or Doro’s online support provides this information. You can also open the SIM compartment and visually compare:
- The standard SIM (the largest) is only used by a few very old models, often limited to 2G.
- The micro SIM, an intermediate format, equips most 4G-compatible Doro flip phones.
- The nano SIM, the smallest, is the format for Doro smartphones running Android like the Doro 8100 or the Leva L30.
Adapters and cutting: what you risk
A plastic adapter allows you to insert a nano SIM into a micro slot. In practice, on a flip Doro, the SIM tray is sometimes narrow, and the adapter can get stuck. It’s better to order the correct format directly from the operator; it’s free or charged a few euros depending on the retailer.
VoLTE compatibility and mobile plan: the criterion that the operator does not check for you
A Doro phone that is 4G compatible on paper will not automatically make VoLTE calls with any plan. VoLTE depends on both the phone and the operator, and not all model/network combinations work.
Low-cost plans (secondary brands, MVNOs) use the network of a major operator but do not always activate VoLTE for all devices. A plan on the Orange network will not necessarily offer the same VoLTE compatibility as a direct Orange subscription.
The checks to make before subscribing:
- Call the operator’s customer service with the exact model reference of the Doro and ask if VoLTE is activated for this device on their network.
- If the operator cannot confirm, test with a borrowed SIM or in-store before committing.
- On the Doro phone, access the mobile network settings and check that the “4G Calls” or “VoLTE” option appears and can be activated.
This point is crucial for seniors who primarily use their Doro for calls. A plan with a lot of mobile data but without functional VoLTE on the Doro will be useless once 2G and 3G are shut down.
Which mobile plan to choose for daily Doro use
Doro phones are designed for use focused on calls, SMS, and limited internet access. A plan with a few gigabytes of data is sufficient in the vast majority of cases. Low-cost offers around a few euros per month largely cover this need.
The real selection criterion is not the data volume but the network coverage at the user’s home and the support for VoLTE. A plan generous in gigabytes on a network that has poor reception in the living area remains a poor choice.
For a Doro used in a residence or rural area, it’s beneficial to check the 4G coverage of the network used by the plan (not just the coverage displayed by the commercial brand, but that of the host operator). The Arcep website offers a coverage map by operator that allows for network-by-network comparison.
Choosing a SIM card for a Doro phone is not limited to format or plan price. Check the phone’s 4G compatibility, confirm VoLTE with the operator, and then choose a plan suited to local coverage: these three steps, in this order, prevent ending up with a silent phone after the shutdown of the old networks.
