Unit upgrades increase the attack and hit points (HP) of a unit type. A new upgrade becomes available in every Age. All unit upgrades take 30 seconds to complete. The cost approximately triples every Age.
In contrast to the previous installments of series, the unit upgrades of every civilization in Age of Empires III usually do not change the original name of the unit, and in most of the cases only add a title word. Royal Guard upgrades are the most common way of changing the units name, although certain improved Church cards also have this effect. Royal Guard upgrades only apply to European and Federal American civilizations, and were not given to other expansion civilizations.
The upgrade effect is always applied to the base units stats, combining additively. Some of the units available in later ages have better base stats because they don't get the early upgrades. This has the effect that their later upgrades are more powerful in comparison.
For African civilizations, the unit upgrades benefit units in groups.
Fortress Age[]
The Fortress Age upgrade, titled Veteran for European and Federal American civilizations, Elite for African and Native American civilizations, and Disciplined for Asian civilizations, adds 20% (25% for Native American civilizations) hit points and attack to the units.
Veteran/Elite/Disciplined upgrades cost 200 wood, 200 coin for European civilizations or 200 wood, 100 coin for Native American and Asian civilizations. Elite upgrades cost 250 wood, 250 coin for African civilizations.
For minor civilizations the cost is 100 wood, 75 coin. For the Aztecs, Quechua, and Haudenosaunee, who have two native warriors, the upgrade costs 150 wood, 100 coin instead.
Industrial Age[]
The Industrial Age upgrade, titled Guard for European and Federal American civilizations, Champion for African and Native American civilizations, and Honored for Asian civilizations, adds 30% (25% for Native American civilizations) hit points and attack to the units, for a total accumulation of +50% hit points and attack.
Guard/Champion/Honored upgrades cost 600 wood, 600 coin for European civilizations, Indian and Japanese; 300 wood, 300 coin for the Chinese; and 400 wood, 200 coin for major Native American civilizations. This includes the Ram and Mantlet for the Haudenosaunee. Champion upgrades cost 800 wood, 800 coin for African civilizations.
For minor civilizations the cost is 400 wood, 300 coin and adds 35% hit points and attack to the units, for a total of +60% hit points and attack. For the Aztecs, Quechua and Haudenosaunee natives who have two native warriors, the upgrade costs 500 wood, 400 coin instead.
Royal/National Guard[]
Some unit upgrades carry the title Royal Guard (European civilizations) or National Guard (American civilizations), which adds 40% hit points and attack to the units instead of 30%, for a total of +60% hit points and attack, and changes their name. This makes a civilization's Royal/National Guard units stronger than other civilizations' Guard units.
Royal/National Guard upgrades cost 750 wood, 750 coin for infantry, cost 850 wood, 850 coin for cavalry.
- Click for a list of Royal/National Guard units and their titles
| Civilization | Units (title) |
|---|---|
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Musketeer (Redcoat) Hussar (King's Life Guard) |
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Halberdier (Stadswacht) Ruyter (Carabineer) |
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Skirmisher (Voltigeur) Cuirassier (Gendarme) |
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Skirmisher (Needle Gunner) Uhlan (Prussian) |
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Culverin (Spingarde) Mortar (Galilean) |
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Crossbowman (Arbalester) Culverin (Basilisk) |
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Salteador (Vigilante) Chinaco (Charro) |
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Deli (Rumeliot) Humbaraci (Ulufeli) |
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Crossbowman (Order Besteiro) Pikeman (Ordinance Pikeman) Musketeer (Legionario) Dragoon (Legion) |
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Cavalry Archer (Dvoryanin) Grenadier (Pavlov) |
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Pikeman (Tercio) Rodelero (Espadachin) Lancer (Garrochista) |
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Pikeman (Dalkarl) Hakkapelit (Drabant) |
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State Militia (Volunteer) |
Artillery[]
Artillery units can be upgraded at the Industrial Age, which adds 25% hit points and attack, and changes the unit's name. They cost 250 food, 250 wood.
These upgrades are available to the cannon units unlocked in the same Age from the Artillery Foundry as well as the Siege Workshop (although the cost of the Light Cannon's upgrade requires food and coin in the same amount, instead of food and wood). However these upgrades do not apply to Factory-produced artillery.
With Knights of the Mediterranean, Royal Guard artillery upgrades were added, with both of Italy's Royal Guard units being artillery. Like Royal Guard infantry and cavalry, these upgrades are more expensive than normal, costing 400 food, 400 wood. However, the upgrades are also weaker than Royal Guard infantry and cavalry, providing only a 10% boost to either attack (Maltese Basilisk Culverins and Italian Galilean Mortars), or hit points (Italian Spingarde Culverins), rather than to both at once.
Imperial Age[]
The Imperial Age upgrade, titled Imperial for European and Federal American civilizations, Legendary for African and Native American civilizations, and Exalted for Asian civilizations, adds 50% hit points and attack to the units, for a total accumulation of +100% hit points and attack (+110% in case of Royal/National Guard units and +75% in case of artillery). This upgrade is also available for the Frigate, Monitor, and Factory-produced artillery, where it is the first upgrade available.
Imperial/Legendary/Exalted upgrades cost 1,500 wood, 1,500 coin for European civilizations, Indians and Japanese. For the Chinese it costs 750 wood, 750 coin per unit. For Asian civilizations, Exalted artillery upgrades cost 1,000 wood, 1,000 coin. Legendaryupgrades cost 2,000 wood, 2,000 coin for African civilizations.
All allied minor civilization units are upgraded for a flat cost of 1,500 food, 1,500 wood through Legendary Native Warriors.
Cost Summary[]
| Age | European Federal Americans |
Native Americans | Asian | Chinese | Africans |
|---|---|---|---|---|---|
| 3 | 200/200 | 200/100 | 200/100 | 200/100 | 250/250 |
| 4 | 600/600 750/750(RG/NG Infantry) 850/850(RG/NG Cavalry) |
400/200 | 600/600 | 300/300 | 800/800 |
| 5 | 1500/1500 | 750/750 | 2000/2000 | ||
Minor native[]
| Age | Minor natives | Aztec Haudenosaunee Quechua |
African Minor natives | Royal Houses |
|---|---|---|---|---|
| 3 | 100/75 | 150/100 | 150/100 | 125/125 |
| 4 | 400/300 | 500/400 | 400/300 | 350/350 |
| 3 | 1500/1500 | |||
Auto upgrades[]
Some units in Age of Empires III upgrade automatically when reaching a new Age instead of the upgrade having to be bought and researched. These units are usually those not trained in the normal way such as the Explorer, or units mainly available at the Home City.
The following units have this trait:
- Heroes
- Pets
- Spy
- Petard
- Sipahi
- Warrior Priest
- Skull Knight
- Tashunke Prowler
- Tokala Soldier
- Native Scout
- Disciple
- Flying Crow
- Urumi Swordsman
- Daimyo
- Shogun Tokugawa
- Yamabushi
- Shinobi
- Consulate units (depending on civilization)
- Nizam Fusilier
- Outlaws if the Wild West, Compunction, Folk Heroes, or Nomadic Bandits technologies are researched
- Eagle Scout
- Priestess
- Chasqui
- Quaker Gun
- Battleship
- Padre
- Levied Spearman
- Levied Bowman
- Levied Gunner
- Sebastopol Mortar
- War Dhow
- Maigadi
- Xebec
- Schiavone
- Papal Guard
- Papal Lancer
- Papal Zouave
- Sacred Band Infantry
