Age of Empires and Age of Empires II
All tributes made in Age of Empires and Age of Empires II have a 30% tribute tax: If a player sends 100 units of a resource, 130 resources will be withdrawn from their resources. The tax has two purposes - first, it simulates how resources become lost on the way in the real world due to corruption, bandits, tariffs, etc. Second, it discourages players from giving huge amounts of resources to allies without any penalization. There are technologies at the Market which lower or even expunge the tribute tax, such as Coinage and Banking. Players should also keep in mind that a least one Market must exist to be able to pay tribute to other players.
If a computer player has the human player set to neutral in Age of Empires, 2,600 or more of any resource (or a combination of resources adding up to 2,600 or greater) can be tributed to that computer player to make it an ally, sometimes resulting in text stating, "Your empire is worthy of my allegiance." However, computer players that have the player set as enemy will never become an ally regardless of how much tribute is given to them. In such cases they will tell the player, "Your petty offerings will not sway my determination to crush your empire!"
In Age of Empires II, in the single player campaign and skirmishes, neutral computer players may request resources in exchange for an alliance with the player; allied computer players may also request resources from the player in order to build up their forces. Players in turn may request resources from computers, which generally comply unless they have none to spare.
The manual for Age of Empires II also suggests sending tribute to enemy players in order to buy off an impending attack; however this is ill-advised, as sending tribute to enemies not only makes them stronger, but also makes them more likely to attack regardless, given the sudden influx of resources at hand.
In multiplayer, the most common use for tribute is to aid more resource-starved team players in bolstering their military or defense.
Age of Mythology
Similarly to the above-mentioned games, all tributes made in Age of Mythology have a tribute tax, but 10% rather than 30%.
Unlike the previous installments, the player does not need to build a Market to be able to pay tribute.
Age of Empires III
In Age of Empires III, the player can send tributes via the in-game options at the top right corner of the screen.
There is a tribute tax of 12%. This means that if a player has 300 food and attempts to give a tribute of 100 food, they will instead lose 112 food. This means that tributes should be used in moderation, lest the player starves themselves in order to boost their allies.
This is even more important to keep in mind than in the other games, as there are no tax-reducing technologies, such as Coinage, that feature in Age of Empires III.