What Are Cuba's Border Crossings Like?
When you enter Cuba the customs official will check your passport and your tourist visa. They will stamp your passport and your visa, and remove the top half of your tourist visa. Save the other half of your tourist visa – you MUST present this when you exit the country.
When you leave Cuba you will be asked if you have anything to declare. You can bring back souvenirs in your baggage, including alcohol and cigars, as long as you do not bring back commercial quantities and do not intend to re-sell any of your purchases. Make sure to keep receipts for everything that you purchase.
You can enter Cuba with 44 pounds (20 kilos) of luggage. When you leave, you can bring an additional 44 pounds of goods, but they must be packaged separately from the rest of your luggage. You can also bring in $501 worth of equipment related to your profession, if you are traveling to Cuba for business reasons. Anything over $501 will be subject to a tax.
Keep in mind that you cannot take any CUC (Cuban Convertible Pesos) with you when you leave. Visitors are not allowed to take more than $5,000 in cash of any currency out of the country.
Once you make your declarations, you and your luggage will be screened to ensure you are not smuggling any prohibited items out of the country. Everything will pass through an X-ray, and police dogs may sniff your luggage. Anything deemed suspicious will be subject to a more thorough search.
Finally, remember that the Cuban government has a ban on anything they consider “obscene or pornographic.” This ban covers many works of literature. If you have any such material, customs officials may confiscate it, in which case you should be able to collect it upon your return.