Visa requirements for Tongan citizens are administrative entry restrictions by the authorities of other states placed on citizens of Tonga. As of 2 July 2019, Tongan citizens had visa-free or visa on arrival access to 123 countries and territories, ranking the Tongan passport 46th in terms of travel freedom according to the Henley Passport Index.
 Tonga signed a mutual visa waiver agreement with Schengen Area countries on 20 November 2015.
 Many countries require a minimum number of blank pages to be available in the passport being presented, typically one or two pages. Endorsement pages, which often appear after the visa pages, are not counted as being valid or available.
 Many African countries, including Angola, Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Democratic Republic of the Congo, Republic of the Congo, Côte d'Ivoire, Equatorial Guinea, Gabon, Gambia, Ghana, Guinea-Bissau, Kenya, Liberia, Mali, Mauritania, Niger, Rwanda, Senegal, Sierra Leone and Togo, South Sudan, Uganda, and Zambia, require all incoming passengers older than nine months to one year to have a current International Certificate of Vaccination or Prophylaxis, as does the South American territory of French Guiana.
 Some other countries require vaccination only if the passenger is coming from an infected area or has visited one recently or has transited for 12 hours in those countries: Algeria, Botswana, Cabo Verde, Chad, Djibouti, Egypt, Eswatini, Ethiopia, Gambia, Ghana, Guinea, Lesotho, Libya, Equatorial Guinea, Eritrea, Madagascar, Malawi, Mauritania, Mauritius, Mozambique, Namibia, Nigeria, Papua New Guinea, Seychelles, Somalia, South Africa, Sudan, Tunisia, Uganda, United Republic of Tanzania, Zambia and Zimbabwe.
 Very few countries, such as Paraguay, just require a valid passport on arrival.
 However many countries and groupings now require only an identity card – especially from their neighbours. Other countries may have special bilateral arrangements that depart from the generality of their passport validity length policies to shorten the period of passport validity required for each other's citizens or even accept passports that have already expired (but not been cancelled).
 Some countries, such as Japan, Ireland and the United Kingdom, require a passport valid throughout the period of the intended stay. 
 In the absence of specific bilateral agreements, countries requiring passports to be valid for at least 6 more months on arrival include Afghanistan, Algeria, Anguilla, Bahrain, Bhutan, Botswana, British Virgin Islands, Brunei, Cambodia, Cameroon, Cape Verde, Cayman Islands, Central African Republic, Chad, Comoros, Costa Rica, Côte d'Ivoire, Curaçao, Ecuador, Egypt, El Salvador, Equatorial Guinea, Fiji, Gabon, Guinea Bissau, Guyana, Haiti, India, Indonesia, Iran, Iraq, Israel, Jordan, Kenya, Kiribati, Kuwait, Laos, Madagascar, Malaysia, Marshall Islands, Mongolia, Myanmar, Namibia, Nepal, Nicaragua, Nigeria, Oman, Palau, Papua New Guinea, Peru, Philippines, Qatar, Rwanda, Samoa, Saudi Arabia, Singapore, Solomon Islands, Somalia, Sri Lanka, Sudan, Suriname, Tanzania, Thailand, Timor-Leste, Tokelau, Tonga, Turkey, Tuvalu, Uganda, United Arab Emirates, Vanuatu, Venezuela, and Vietnam.
 Countries requiring passports valid for at least 4 months on arrival include Micronesia and Zambia.
 Countries requiring passports with a validity of at least 3 months beyond the date of intended departure include Azerbaijan, Bosnia and Herzegovina, Honduras, Montenegro, Nauru, Moldova and New Zealand.
Similarly, the EEA countries of Iceland, Liechtenstein, Norway, all European Union countries (except the Republic of Ireland) together with Switzerland also require 3 months validity beyond the date of the bearer's intended departure unless the bearer is an EEA or Swiss national.
 Countries requiring passports valid for at least 3 months on arrival include Albania, North Macedonia, Panama, and Senegal.
 Bermuda requires passports to be valid for at least 45 days upon entry.
 Countries that require a passport validity of at least one month beyond the date of intended departure include Eritrea, Hong Kong, Lebanon, Macau, the Maldives and South Africa.
 Some countries, including Australia, Canada, Fiji, New Zealand and the United States, routinely deny entry to non-citizens who have a criminal record while others impose restrictions depending on the type of conviction and the length of the sentence.
 The government of a country can declare a diplomat persona non grata, banning entry into that country. In non-diplomatic use, the authorities of a country may also declare a foreigner persona non grata permanently or temporarily, usually because of unlawful activity.
 For example, Azerbaijan bans visits by foreign citizens that have previously entered Azerbaijan through non-Azerbaijani controlled borders. This includes the illegal entry into the separatist region of Nagorno-Karabakh (the de facto independent Republic of Artsakh), its surrounding Armenian-occupied territories, and the Azerbaijani exclaves of Karki, Yuxarı Əskipara, Barxudarlı, and Sofulu which are de jure part of Azerbaijan but under the control of Armenia. Foreign citizens who enter these territories will be permanently banned from entering the Republic of Azerbaijan and will be included in their "list of personae non gratae". As of 2 September 2019, the list mentioned 852 people.
 Kuwait, Lebanon, Libya,  Syria, and Yemen do not allow entry to people with passport stamps from Israel or whose passports have either a used or an unused Israeli visa, or where there is evidence of previous travel to Israel such as entry or exit stamps from neighbouring border posts in transit countries such as Jordan and Egypt. 
 To circumvent this Arab League boycott of Israel, the Israeli immigration services have now mostly ceased to stamp foreign nationals' passports on either entry to or exit from Israel (unless the entry is for some work-related purposes). Since 15 January 2013, Israel no longer stamps foreign passports at Ben Gurion Airport. Passports are still (as of 22 June 2017) stamped at Erez when passing into and out of Gaza.[citation needed] 
 Iran refuses admission to holders of passports containing an Israeli visa or stamp that is less than 12 months old.
 Several countries mandate that all travellers, or all foreign travellers, be fingerprinted on arrival and will refuse admission to or even arrest travellers who refuse to comply. In some countries, such as the United States, this may apply even to transit passengers who merely wish to change planes rather than go landside.
 Fingerprinting countries/regions include Afghanistan, Argentina, Brunei, Cambodia, China, Ethiopia, Ghana, Guinea, India, Japan, Kenya (both fingerprints and a photo are taken), Malaysia upon entry and departure, Mongolia, Paraguay, Saudi Arabia, Singapore, South Korea, Taiwan, Thailand, Uganda, the United Arab Emirates and the United States.
 Many countries also require a photo be taken of people entering the country. The United States, which does not fully implement exit control formalities at its land frontiers (although long mandated by domestic legislation), intends to implement facial recognition for passengers departing from international airports to identify people who overstay their visa.
 Together with fingerprint and face recognition, iris scanning is one of three biometric identification technologies internationally standardised since 2006 by the International Civil Aviation Organization (ICAO) for use in e-passports and the United Arab Emirates conducts iris scanning on visitors who need to apply for a visa. The United States Department of Homeland Security has announced plans to greatly increase the biometric data it collects at US borders. In 2018, Singapore began trials of iris scanning at three land and maritime immigration checkpoints.
 1 British Overseas Territories. 
2 These countries span the conventional boundary between Europe and Asia. 
3 Partially recognized. 
4 Unincorporated territory of the United States. 
5 Part of the Kingdom of Denmark.
6 Egypt spans the boundary between Africa and Asia.
 1 British Overseas Territories.
2 Azerbaijan, Georgia, Turkey, Kazakhstan, Russia and the partially recognised republics of Abkhazia and South Ossetia each span the conventional boundary between Europe and Asia.
3 Cyprus, Armenia, and the partially recognised republics of Artsakh and Northern Cyprus are entirely in Western Asia but have socio-political connections with Europe.
4 Egypt spans the boundary between Africa and Asia.
5 Partially recognized.