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Catan Trading & Port Rules
Understand domestic trading, 4:1 bank exchanges, generic 3:1 harbors and resource-specific 2:1 harbors with practical examples.
Without a port, exchange four of one resource for any one resource. Generic harbors improve the rate to 3:1, and specialized harbors to 2:1 for their pictured resource.
Catan trading: Exchange four matching resource cards for one of your choice at the normal bank rate. A settlement or city at a harbor improves maritime trading to 3:1 or the indicated 2:1 resource rate.
How Catan trading rates work
Catan offers two kinds of resource trading: domestic trading with another player and maritime trading with the supply. Harbor discounts only affect maritime trades.
4:1 — Standard bank trade
Exchange four cards of the same resource type to take one resource of your choice, even without a harbor.
3:1 — Generic harbor
Control a generic harbor with your settlement or city to exchange three cards of any one resource type for one resource of your choice.
2:1 — Specialized harbor
Control a harbor showing a particular resource to exchange two cards of that resource for one resource of your choice.
Domestic trading: who can trade?
On your turn, you may offer resource cards to opponents and negotiate exchanges. Other players can accept or reject your offers; two non-active players cannot trade independently during your turn. Normal domestic trades exchange resource cards and do not permit giving cards away for nothing.
Can you trade without a port?
Yes. For example, give the supply four brick cards and take one wheat. You may not combine two brick and two wool to make a 4:1 trade.
What does it take to use a Catan harbor?
You must own a settlement or city on one of that harbor’s marked coastal intersections. A road running past the port does not activate it. Having a city rather than a settlement does not improve the rate further, and different harbor discounts cannot be combined.
Valid and invalid trade examples
Valid
Give three ore for one lumber while controlling a generic 3:1 harbor.
Invalid
Give one ore, one brick and one wool as a 3:1 trade. The cards must match.
Invalid
Use a 2:1 lumber harbor to exchange two wheat. That harbor only discounts lumber.
When can you trade in Catan?
Under the current base-game structure, trading and building take place during your turn after resource production. When you legally build on a harbor, you may use its rate during your trading phase. Refer to your edition’s rules when older printings or variants sequence these actions differently.
Frequently asked questions
Can I trade with the bank if I do not have a harbor?
Yes. The default rate is 4:1.
Can I trade with another non-active player?
No. Domestic trades during a turn must involve the active player.
Does a city improve the harbor rate?
No. A city and a settlement give the same access to the harbor’s printed rate.
Can I mix resource cards to reach 3:1?
No. All three offered cards must be the same resource type.