Lucky you; in the Fall of 2016 the restrictions on Cuban cigars and rum were lifted, and Americans can bring them into the US from their trip abroad, as long as the goods are for personal consumption (which includes gifts for others). The previous limitations on monetary value were removed, but they are still subject to the customs rules of both countries, when leaving Cuba and when returning to the United States.
According to Cuba’s border control authority, Aduana General de la República:
What can I take in my baggage while leaving the country?
Passengers have the right to export:
- Personal belongings.
- Items and objects temporarily imported and now re-exported, proved by the document given to them by Customs when arriving in the country.
- An amount up to five thousands (5000) USD (See regulations of the Central Bank of Cuba)
- Items legally purchased in the country, a reasonable amount indicating non-commercial purposes and which are not subjected to any regulation, and if requiring a permit or authorization, it shall be submitted to Customs.
Note: in Spanish, the section on what can be exported, dated 2014, lists 3 bottles of liquor and 200 cigars. The more recent February 2018 version in English makes no mention of limits. Save and carry invoices, should Cuban authorities check.
On returning to the US, the $800 exemption per person applies, beyond which duty is levied, the same as for alcohol and tobacco from other countries: as many as 100 cigars and 1 litre of rum (several bottles).
US Customs and Border Protection explains all (added emphasis mine):
CBP Public Notice on Process for Imports from Cuba
31 C.F.R. § 515.582 authorizes importations of goods produced by independent Cuban entrepreneurs, as set forth on the State Department’s Section 515.582 List without a limitation on the value of the goods. However, these goods are still subject to the applicable provisions of the HTSUS. Imports by private individuals authorized under § 515.582 of the CACR are allowed an $800 exemption from customs duties in accordance with the HTSUS, if the goods are for personal use. The first $1,000 above that $800 will be assessed duty at rate of 4%, pursuant to the HTSUS. The $800 exemption and the application of the 4% duty rate for the first $1,000 above the $800 exemption will be multiplied by the number of qualified family members traveling. So, for example, a qualified family of three would be eligible for a $2,400 exemption from duty, and the $3,000 above that would receive a 4% duty rate. Please be aware that CBP may deem goods accompanying passengers in excess of these values as a commercial shipment and treat them according to the commercial procedures in the above paragraph.
Importing/Bring Cuban cigars to the U.S. for personal use.
Travelers bringing in tobacco products (Cigarettes, Cigars, Bidis) into the U.S. for personal use.
Bringing alcohol (including homemade wine) to the U.S. for personal use