Phone service

An international telephone number usually consists of the international dialling prefix, a country code, an area code and the local number.

The international dialling prefix is usually shown as a leading "+" in phone numbers. The relevant prefix is automatically substituted for the "+" on mobile phones and most other smart dialling devices, but must be typed in from most landline phones. Sometimes there are several prefixes to choose from. The prefix "00" will work in most of Europe (including all of EU), "011" in the US and Canada, "0011" in Australia. If you've got a phone number starting with the "+" and the country code, and want to use that number from a local land line, you usually need to replace those with the "trunk prefix" (often "0"), and if you call within the area code area, you often have to dial the local part only. The international form should work as such from mobile phones. With mobile phones you should instead watch out when calling home, as numbers saved in your local format may not have the appropriate international prefix added by your phone, so you may end up calling local numbers.

The country codes are listed in List of country calling codes, and the relevant one in country articles' sidebar (near the top) and Connect section (near the end). Some territories have special arrangements, not using their country's country code.

The area code traditionally connected the call to a regional exchange, which knew where to direct the call locally. Nowadays they are mostly a convenience for placing local calls, or just a left-over from the analog era. Similar codes can be used for special numbers or different mobile operators, and are usually treated as mandatory area codes when placing a call. In many countries the area code is prefixed by a trunk prefix (often "0"), which should be left out when using the country code. In some countries all the area code should be retained.

The local part is what comes after the area code. In many countries only this part is to be dialled when placing calls inside the area. The area code can be used also then in some countries.

Mobile phones are seldom bound to a specific area and thus usually have no real area code (for exceptions in a few countries, see relevant Connect sections). The mobile phones know how to call a number given in the full international form, with leading "+" and country code. Entering all numbers in this form avoids confusion when crossing borders. Some numbers that can be reached only locally don't have an international form. This includes some service and emergency numbers.

The Wikivoyage guides give all numbers in the international form, if there is one. Directions on how to convert those numbers to ones usable from local landline phones, and how to convert numbers as written locally to the international form, are usually given in the country articles' Connect sections.

Parenthesis, blanks and hyphens are often used when writing phone numbers. These are for clarity only, and are ignored when placing a call. On Wikivoyage, the local part of phone numbers is often given in parts joined by hyphens, while country code, area code and local part are separated by blanks.

Main article: Mobile phones

You may be able to bring your mobile phone and use it either with billing through your home carrier ("roaming") or by obtaining a SIM card from a local provider. Another option is to buy an inexpensive low-end prepaid handset at destination.

Depending on the length of your trip, it may make sense to buy a local pre-paid mobile telephone, an unlocked phone and a local SIM, or a local SIM card for use in your existing mobile device. Roaming with your existing phone may be manageable when visiting one European Union country from another, but further abroad the cost may be prohibitive or the service not available. Many prepaid handsets will not roam at all. In most of Europe a pre-paid SIM card is usually very cheap (€10 or less with some credit included). In some countries (e.g. Italy) users may need to present identification or a local tax code to buy one.

There are multiple, incompatible mobile phone systems (GSM, CDMA, UMTS) and the frequencies used also vary from one continent to another, and between countries and operators among those used on the continent. Some phones can cope with more networks than others. Some handsets are locked to one provider, making them unusable with a local SIM card unless unlocked.

If you have a smartphone, there are lots of travel-oriented apps to make your trip easier.

If you are going to be out of range of a telephone, but still want to receive calls, voice mail may be an option. Most telephone service providers offer a voice mail option, usually as an add-on to an existing land line, pager, mobile or Internet-based telephone number. Some offer it as a stand-alone service.

You can usually check your voice mail remotely; obtain the access number and login details from your voice mail provider before leaving home.

Many hotels and motels charge set rates for all calls made from in-room telephones, much higher than for residential or business phones. Some even charge for calls to toll-free numbers (such as 800 number). A few have been known to block calls to telco services like Bell Canada's "Canada Direct" or (more rarely) fraudulently redirect them to another provider who immediately asks for a credit card number. Check the call rates before making a call; upscale and sometimes even budget hotels may charge US$35/min or more for international calls.

Hotels and motels usually do not charge for voice calls you receive. Check for any received telephone charges before giving out a hotel or motel telephone number for people to call you.

Usually there are charges for received faxes.

As most hotels now provide some form of broadband Internet, it may be cheaper to run a voice-over-IP application on a portable device instead of using the telephone in the room. Budget hotels usually include Wi-Fi in their base price, while many high-end properties charge substantial extra hidden fees.

A rare few business hotels offer packages that include complimentary unlimited local and toll-free calls.

If in doubt, be sure to enquire before checking in.

If you can use a phone of a private host, be aware of costs of international calls. For some, they might be a significant expense, and regardless, they are an additional expense in lodging you. Pay them if you can; otherwise try to compensate them in a suitable way.

Main article: Internet telephony

Where you have full access to the Internet at a reasonable speed, making phone calls over the Internet (VoIP) is the cheapest option. Free calls are usually possible if you have compatible calling software or apps installed on your respective devices, are online at the same time, and don't pay for the data transfer. If you pay for the airtime, VoIP may still be cheaper than ordinary calls in some scenarios.

A voice call over Internet requires a good-enough internet connection, a way to get contact over internet to the device to be called, and suitable software (and the voice hardware, included in any phone and most laptops). You may pay for use of internet, and you may pay for the operator setting up the call.

Applications for the standard session initiation protocol (SIP) are available both for laptop PC's and small mobile devices like those running Android. Unlike a cellular phone (which incurs substantial "roaming" charges when taken out of its home region), calls to your device will be directed over the internet, the cost of which in the broadband case seldom depends on the amount of traffic. However, if your connection is via the mobile phone network or a satellite connection, the per megabyte cost may be heavy.

If your smartphone has Wi-Fi, making cheap phone calls may be as easy as installing a free app (either a generic SIP client, or a programme for one specific provider like Skype or Viber) and visiting a Wi-Fi hotspot. Similar "softphone" software run on laptops or tablets using the built-in microphone and loudspeakers. Nonetheless a headset with a boom microphone gives better audio.

To be able to place calls on the public telephone network you need a telephone number, and thus an operator providing one, while end-to-end VoIP just requires the other end to run SIP software (or a proprietary equivalent) and not to be behind a firewall blocking the call.

The quality of Internet telephone connections varies widely, based on the underlying network connection. Some publicly available networks can block VoIP, some have very high latency, some are unreliable (dropping too many packets), many are simply too slow, and in some countries Internet telephony can be blocked entirely to protect the revenues of national phone companies. Etisalat, the state-owned telecommunications provider of the United Arab Emirates, has been blocking access to Skype entirely; some hotels in the UAE may provide access through 'TheWayOut' Wi-Fi service.

You should install a VoIP app and select a voice service provider (VSP) to test your configuration before departing.

It may be possible to rent a computer with Skype from a local Internet store.

While still around, pay phones are diminishing in number and most are able to place outbound calls only. Trunk or toll calls tend to be expensive, with high initial minimums. Some cost saving may be possible using prepaid calling cards (which are necessary for some of the phones).

Coin-paid long-distance calls were traditionally operator-assisted, so they carry the worst rates. A call which only reaches voicemail will still incur the full toll, even though there's no means for the other party to return the call.

Check the information in the booth before making a call, especially with payphone booths not branded by a major carrier. While sometimes an obscure third-party provider is cheaper, often specialist providers charge higher fees or a substantial minimum. These can be a rude surprise if you pay by credit card.

Often, courtesy phones at airports and similar places will ringdown a specific taxi or similar traveller services. Look out for these so you may not need to use a pay phone.

Some flights offer phone service via an in-seat phone. These typically cost around US$5/minute for a voice call, or US$2 per SMS.

If you have access to a phone, but want to avoid paying the local rates of international calls (or have your host pay them), you may be able to get codes to use for placing calls via a local (possibly toll-free) number.

Note the local emergency number, often uniform across many countries, often 112 as in the European Union, 911 as in the U.S.A. or 999 as in the UK. No area codes are needed with these three numbers or local equivalents (and may not work). In some remote areas, you may need to call a local normal-looking number.

All, one or some of these, and possibly other emergency numbers, may be specially handled: in the GSM standard, dialling 112 – or any emergency number known to the phone – will connect directly to the emergence services bypassing the normal call routing (and possible queueing), often using any network available regardless of roaming contracts.

Many mobile phones allow calling 112 without unlocking the phone (just give those numbers when asked for a PIN and the phone might offer to call the emergency services, and the call may succeed even when you have no credit or even no SIM (in some countries you then need to additionally type "55" or wait a while to get to the operator). From landlines, the emergency number may bypass the local exchange.

If you call an emergency number by accident, you may want to stay on the line to tell it was a mistake, and otherwise be ready to answer any check-up calls from the emergency centre.

In many countries, 112, 911 or 999 can be used even when there are other recommended emergency numbers for different kinds of emergencies.

The emergency number may connect you to personnel who will summon the assistance you need themselves, or they may forward the call to the appropriate department. In some countries you are expected to know what assistance you need, while in others it is the staff that will make such decision based on how you answer their questions. If some questions seem senseless, try to stay calm and just answer. They may give you advice on how to handle the situation until help arrives.

The operators may be able to tell your location from your phone number, either directly or by computations based on mobile base stations and other available information, depending on the phone and the network. The latter may be legally allowed only in certain situations, and may require bureaucracy.

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