Trade income

A settlement's trade income is the total of all its trade routes. Routes run over land and over sea. The ships sailing on the campaign map show the sea routes; they earn nothing themselves. A richer route has more ships on it.

What makes a route worth more

• Goods the other side lacks. A good only counts if the partner does not have it. Each trade good has a trade value, and more of it is worth more.
• Population. Two big towns trade a little more than two small ones. Goods matter far more.
• Trade bonus. Every point of trade bonus a settlement has adds 10% to all its routes. Building pages list these points as "trade income". They come from Traders and many industries. Traders give inland settlements far more than coastal ones: +15 to +20 at the top level, against +5. Governors with trading skills add their bonus on top. The total can go below zero, and then the town earns less than its routes' base value.
• Who the partner is.

Partner	Land route	Sea route
Your own settlements, allies, protectorates, factions you have trade rights with	full value	full value
Any other faction	⅓	½
A faction you are at war with	nothing	nothing

Land trade

• A settlement trades with every neighbouring settlement across a land border. Rebel settlements do not trade.
• Goods you send count twice as much as goods you receive.
• Distance does not matter.
• Roads multiply land routes, but only as far as the neighbour's roads allow:

Your roads	Neighbour has no roads	Neighbour has Roads	Neighbour has Paved Roads or Highways
Roads	×1	×1	×1
Paved Roads	×1	×2	×2
Highways	×1	×2	×3

Sea trade

• The port sets how many sea routes a settlement has:

Port	Sea routes
Trade Port	1
Shipwright	2
Dockyard	3
The Cothon of Carthage	3

Three is the most any settlement can have.

• Each route goes to the most profitable port in reach, not the nearest. Own and allied ports usually win, because foreign ones count at half value. The partner must have a port.
• A settlement never trades by sea with a neighbour it already trades with over land.
• Longer voyages are worth less: a port twice as far away is worth half as much.
• Goods sent by sea count once, not twice as on land.
• The receiving port earns 20% of the route as an import, on top. The sender keeps the full value. At the start of the campaign, Rome's sea route to Capua earns Rome 288 and Capua 58.
• When two ports pick each other, each earns its own route plus 20% of the other's.

What cuts trade

These come from each settlement's Region Information building:

• Blockaded: −10 trade bonus (−100%).
• Under siege: −5 trade bonus (−50%) and a lower trade level. Both linger for a few turns after the siege is lifted.
• No government building: −15 trade bonus (−150%) until a government is built or being built.
• Empire size: in an empire of 2 or more settlements, every settlement loses trade bonus. Settlements without a Governor's Palace lose 1. Settlements with a Governor's Palace or higher lose more as the empire grows:

Settlements in your empire	Trade bonus lost with a Governor's Palace
2–4	−2
5–29	−3
30–100	−4
101–400	−5
401 or more	−6

Raising trade income

1. Hold goods your neighbours do not have.
2. Build roads at both ends of a land route. Highways pay ×3 only next to Paved Roads or better.
3. Stay at peace with trade partners, and get alliances or trade rights.
4. Build ports up to Dockyard for three sea routes.
5. Build Traders and industries that give trade bonus, enough to outweigh the empire-size loss.
6. Your capital gains +2 trade bonus while Jewellery Exports or Spices Exports is built anywhere in your empire.