A customs and monetary union is a type of trade bloc which is composed of a customs union and a currency union. The participant countries have both common external trade policy and share a single currency.

Customs and monetary union is established through trade pact.

Note: Every economic and monetary union has also a customs and monetary union.

Additionally the autonomous and dependent territories, such as some of the EU member state special territories, are sometimes treated as separate customs territory from their mainland state or have varying arrangements of formal or de facto customs union, common market and currency union (or combinations thereof) with the mainland and in regards to third countries through the trade pacts signed by the mainland state.