Is it legal for a US citizen to travel to Cuba?

Strictly speaking travelling to Cuba isn’t illegal. The US doesn’t have exit controls, so it’s citizens are allowed to travel wherever in the world they want. What the US does have is a very strict embargo with Cuba. Effectively this means in order to travel to Cuba a US citizen or resident needs a licence to spend money there.

These licences, which authorize certain travel related transactions, are only granted for certain kinds of travel. Specifically 31 CFR 515.560, the regulation authorizing the licences, only allows transactions related to the following activities:

(1) Family visits (see §515.561);

(2) Official business of the U.S. government, foreign governments, and certain intergovernmental organizations (see §515.562);

(3) Journalistic activity (see §515.563);

(4) Professional research and professional meetings (see §515.564);

(5) Educational activities (see §515.565);

(6) Religious activities (see §515.566);

(7) Public performances, clinics, workshops, athletic and other competitions, and exhibitions (see §515.567);

(8) Support for the Cuban people (see §515.574);

(9) Humanitarian projects (see §515.575);

(10) Activities of private foundations or research or educational institutes (see §515.576);

(11) Exportation, importation, or transmission of information or informational materials (see §515.545); and

(12) Certain export transactions that may be considered for authorization under existing Department of Commerce regulations and guidelines with respect to Cuba or engaged in by U.S.-owned or -controlled foreign firms (see §§515.533 and 515.559).

And this is what the licence permits you to do:

(c) Persons generally or specifically licensed under this part to engage in transactions in connection with travel to, from, and within Cuba may engage in the following transactions:

(1) Transportation to and from Cuba. All transportation-related transactions ordinarily incident to travel to and from (not within) Cuba are authorized.

(2) Living expenses in Cuba. All transactions ordinarily incident to travel within Cuba, including payment of living expenses and the acquisition in Cuba of goods for personal consumption there, are authorized.

(3) Importation of Cuban merchandise. The purchase or other acquisition in Cuba and importation as accompanied baggage into the United States of merchandise with a value not to exceed $400 per person are authorized, provided that no more than $100 of the merchandise consists of alcohol or tobacco products and the merchandise is imported for personal use only. […]

(4) Carrying remittances to Cuba. […]

(5) Processing certain financial instruments. […]

Note that its not the travel itself that permitted by the licence, it’s the transaction that pays for the transportation to or from Cuba that it permits.

Also note the the regulation specifically excludes tourists:

(f) Nothing in this section authorizes transactions in connection with tourist travel to Cuba.

Hopefully this might change in the future, but as allowing tourist travel would require an act of Congress, don’t hold your breath. In the meantime, if you’re curious what could happen to someone from the US who travels to Cuba without a licence:

§501.701 Penalties.

…

(1) Persons who willfully violate any provision of TWEA or any license, rule, or regulation issued thereunder, and persons who willfully violate, neglect, or refuse to comply with any order of the President issued in compliance with the provisions of TWEA shall, upon conviction, be fined not more than $1,000,000 or, if an individual, be fined not more than $100,000 or imprisoned for not more than 10 years, or both; […]

Note that TWEA stands for “Trading With the Enemy Act”. As Cuba has been designated a state supporter of terrorism, I believe the sentencing guidelines would require a fairly long prison term for anyone convicted.

Though as a practical matter my understanding is that an American tourist who travels to Cuba via Mexico or Canada is very unlikely to be caught.

According to the US Department of State,

Tourist travel to Cuba is prohibited under U.S. law for U.S. citizens and others under U.S. jurisdiction.

Legally traveling to Cuba as a US Citizen requires a reason specified under one of several types of licenses to do so.

General & Specific Licenses for Travel: The U.S. Department of the Treasury’s Office of Foreign Assets Control (OFAC) has issued general licenses within the 12 categories of authorized travel for many travel-related transactions to, from, or within Cuba that previously required a specific license (i.e., an application and a case-by-case determination). Travel-related transactions are permitted by general license for certain travel related to the following activities, subject to criteria and conditions in each general license: family visits; official business of the U.S. government, foreign governments, and certain intergovernmental organizations; journalistic activity; professional research and professional meetings; educational activities; religious activities; public performances, clinics, workshops, athletic and other competitions, and exhibitions; support for the Cuban people; humanitarian projects; activities of private foundations or research or educational institutes; exportation, importation, or transmission of information or information materials; and certain authorized export transactions. No further permission from OFAC is required to engage in transactions covered by a general license.

(emphasis mine)

Recently, however, there has been a warming of relations between Cuba and the US, with some of the events shown in this New York Times page. Perhaps soon, relations will normalize to the point that we might vacation in Havana.