The first key indicator of the degree of coverage or inclusiveness of external voting is related to the requirements—for citizenship, residency, voter registration or other—that must be met before a person can be entitled to an external vote. These requirements may change significantly from one context to another. In many cases they do not merely reproduce the normal requirements for an individual to exercise his or her political rights within the country, but also include some special or additional requirements related to the situation of the potential voter abroad.
Countries and territories which restricted entitlement to an external vote according to activity abroad

When there is no special or additional requirement linked to the circumstances or personal situation of the potential voter abroad, a guarantee of universal access can be assumed in the sense that external voting is accessible to all citizens whether, for example permanently or temporarily abroad. The most common and widespread requirement, although not the only one, is that of citizenship, although there are exceptions. New Zealand, for example, recognizes citizens of other countries as external electors if they are permanently resident in New Zealand: they do not need to be New Zealand citizens in order to qualify as external electors. From this perspective New Zealand would be considered the most inclusive case.
In a majority of the 115 countries and territories the legislation on external voting does not include any special or restrictive requirement for individuals to be eligible for an external vote. In others, there are formal limitations on eligibility for an external vote, mostly relating either to the circumstances of the stay abroad (activity-related restrictions) or to the length of time for which the citizen has been out of the country (length of stay abroad restriction).
South Africa can stand for an example of the first type of requirement but has very particular features: it introduced external voting for its diaspora overseas for its historic elections of 1994 in very comprehensive terms, but since then has been restricting external voting in a systematic way. For the general elections of April 2004 it restricted external voting to members of the diplomatic corps and voters who were already registered in the country and would be abroad only temporarily. Interestingly, the law does not specify what temporary absence from South Africa involves, but it does give the parameters of when and how to register and apply for an external vote. Restricting external voting to diplomatic staff or to those employed by the government is a fairly common type of activity-related restriction: it is found, for example, in Bangladesh, Ireland, Israel, Laos and Zimbabwe. It also common to allow those who are in the armed forces, students or citizens involved in other official or international work to vote from abroad.
The second type of restriction concerns the length of stay abroad. This restriction can also take different forms. In most of these countries there is an upper limit to the time the voter can stay abroad before they lose their voting rights. The maximum time abroad in Guinea, for example, is 19 years, while Australia’s limit is six years, although an extension can be requested in this case. The Falkland Islands allows voters abroad to vote only if they are abroad temporarily, and only if they are residing in the United Kingdom (UK) and nowhere else. The governor of the Falkland Islands has to make a series of administrative arrangements for conducting the ballot abroad. The maximum length of stay abroad for Germans is 25 years, for the UK 15 years, for Canada five years and for Turkey six months.
The length of stay abroad restriction can also work the opposite way, meaning that a voter needs to be away from his or her country for a certain period of time in order to be able to vote from abroad. This is the case for voters from Chad, for example, who need to register in a consular registry at least six months before the election. External electors from Mozambique need to have been resident abroad for at least one year before the electoral registration process begins in there. Unless the voter has been abroad for at least six months and registered at a diplomatic mission, he or she can only vote if appointing a proxy. Gibraltar, Guernsey, the Isle of Man and Jersey allow external voting only for a provisional stay abroad, and registration for elections can only take place within the territory. Senegalese voters need to reside abroad for at least six months to have external voting rights, and external voting and registration can only take place in countries where Senegal has a diplomatic mission.
Some examples of countries and territories which restrict entitlement to an external vote according to the length of stay abroad

Cases where external voting is legally or practically restricted to voters who are only temporarily out of the national territory are in the minority. More often because of technical or administrative limitations than for strictly legal reasons, it is most common for external voting not to be provided for people who are only out of their country on a temporary basis, whether for work, for business, for study, or for medical or recreational reasons. Australia, Canada, Denmark, New Zealand and Norway are among the few countries that offer facilities to voters who are in transit travelling or provisionally abroad. Either their electors are not required to register specifically as voters abroad, or they can ask to register as such up to a few days before the period stipulated for voting.
However, there are also some other forms of restriction on external voting. Even for the approximately 80 countries and territories that do not specifically restrict the entitlement to an external vote, there is no guarantee that all eligible voters will be entitled to vote. Their exercise of this right can be hindered or limited by other kinds of legal requirement, such as those necessary before a person can register as a voter, or by technical, administrative or operational provisions related to electoral registration or voting itself. Administrative obstacles may, for example, involve difficulties in accessing or posting ballot papers. Some other restrictions are discussed below.
The Philippines case deserves particular attention because it is the only country where there are special requirements for the eligibility and entitlement to vote of certain categories of citizens abroad, although these requirements do not apply for ordinary citizens abroad. There are special requirements for natural-born Filipinos who became naturalized citizens of another country but wish to re-acquire their Philippine citizenship according to the 2003 Act on Citizenship Retention and Re-acquisition, including a one-year residency in the country. In addition, there are special requirements for Filipinos abroad who are recognized as immigrants or permanent residents by another country. Such individuals are required to sign an affidavit of intention to return and resume actual residence in the Philippines no later than three years from approval of their application for registration as ‘overseas’ voters.
There are other administrative and technical requirements or conditions which, even though they do not formally restrict entitlement to an external vote, can have a considerable and even decisive influence on the ability or opportunity to exercise the right to vote from abroad. The requirements and conditions for proof of identity to register as an external elector are particularly important in this context. The more rigorous the requirements for verifying identity and registering as a voter abroad, and the more difficult this is to do or the shorter the time period allowed for doing so, the more restricted the coverage of the potential external electorate will be. For example, when the United Nations Transitional Authority in Cambodia (UNTAC) allowed external voting for the elections to the Constituent Assembly in Cambodia in 1993 it made it conditional on a voter having registered previously within the country, and finally set up polling centres only in Paris, New York and Sydney, which drastically reduced its inclusiveness.
The documents needed to prove that a person satisfies the eligibility requirements, and therefore can register as an external elector, can be especially important for those potential voters who because of their migratory status or the length of their stay in the host country might not have them or might face difficulties in obtaining them. For its first application of voting from abroad in 2006, Mexico allowed only those citizens who were provided with a voting card issued (free) by the electoral authority, but only within the country, to vote externally. Some countries require external electors to show a valid visa before they are allowed to vote.
In similar vein, if the procedure for registering as an external elector has to be carried out at an embassy or consulate, the extent and geographical distribution of the country’s network of diplomatic missions overseas and the distance between the diplomatic missions and the regions or zones where the potential electorate resides and/or works could have a negative influence on the coverage of the mechanism for external voting.
By contrast, if the requirements for verifying the voter’s eligibility and for registering as an external elector are reasonable for any citizen, and if the citizen has ample material facilities or time in which to register (for example, to request, replace or update the required documents at the home country’s diplomatic missions abroad or by post, or possibly by electronic means), this will undoubtedly favour an increase in the participation of external voting in many cases.
Registration for the Afghan presidential election of 2004 provided an interesting case. External voting was conducted only in the two neighbouring countries where most of the Afghan refugees were located—Iran and Pakistan. A large number of Afghan voters residing in Iran were not registered by the representatives of the Afghan electoral authorities, but were eligible to vote by reference to their Iranian refugee registration document.