Geographic numbering and portability: what they are and how they work

When a business signs up for telephony, two concepts come up again and again: geographic numbering and portability. Understanding them helps you choose the right numbering and know what to expect when you change operators.

What geographic numbering is

Geographic numbers are those whose prefix identifies the geographic area —the province— the line is associated with. In Spain they are part of the National Numbering Plan, have 9 digits and start with 9 or 8, with the second digit other than 0. The prefix (for example, 91 for Madrid, 93 for Barcelona or 95 for Málaga) indicates the geographic origin of the number.

Unlike mobile numbers (which start with 6 or 7) or premium-rate numbers, a geographic number conveys proximity: a customer who sees a number with their provincial prefix perceives the business as local, even if the team works remotely or from the cloud.

How it is assigned

Operators request blocks of geographic numbering from the CNMC (Spain's telecoms regulator) through its electronic office, by province. These blocks were traditionally 10,000 numbers, although the CNMC allows blocks of 1,000 when there are justified reasons. The operator then assigns those numbers to its customers.

One important point: geographic numbering is tied to the province of the prefix. It is not a "decorative" number: using a landline number from a province requires a genuine link to that area (an address or establishment). This requirement has been reinforced by recent regulations against telephone fraud.

What number portability is

Portability is the right to keep your phone number when you change operators. It is free, and the process is handled by the receiving operator (the new one), which requests the migration from the donor operator (the previous one).

An interesting consequence of portability is that the prefix no longer identifies the operator: a number starting with 95 may today belong to any company, because its holder has ported it over time. The prefix still indicates the province of origin, but not the brand providing the service.

What this means for your business

• You can keep your existing number when moving to a virtual PBX; you don't lose the telephone identity your customers already know.
• You can hold numbering from several provinces to project a local presence in different areas, managing it all from a single cloud PBX.
• Geographic numbering builds trust: customers recognise the prefix and are more likely to pick up.

At Virtual Voz we handle both the portability of your current numbering and the assignment of new geographic numbering, integrated into your virtual PBX. If you want to keep your number or expand your presence to new provinces, get in touch and we'll advise you.