HOI IV - Open Beta Update V

✦AI summary1w

Open Beta Update V focuses on AI naval behavior improvements, stability fixes for large-scale naval battles, and various quality-of-life adjustments to lend-lease and supply tooltips.

Images © Hearts of Iron IV via Steam

▲Buffs4

Naval AIThe AI will now train ships more opportunistically.
EnglandBattleship Construction:Fixed a bug that prevented England from building improved battleships.Blocked→Enabled
USAAircraft Carrier Construction:Fixed a bug where the USA was unable to build 1940 aircraft carriers.Blocked→Enabled
Army AIThe AI will now train their troops more frequently, leading to better quality divisions.

✚Bug fixes4

Supply SystemFixed a bug where ships were partially considered for supply needs, correcting logistics calculations.
Naval AIStrike Force:Fixed a bug where strike forces would get stuck on invalid targets and cease functioning.
ItalyRI Bolzano:RI Bolzano in the 1939 OOB now correctly uses the Bolzano Class hull.Incorrect→ship_hull_cruiser_2
Winter WarfareFixed incorrect snow modifier values and the leader snow adjuster functionality.

◆Other changes7

Lend LeaseLend lease now defaults to the maximum amount for 'once' and 100% for 'percentage' modes, reducing manual input.→Max/100%
Supply SystemUpdated supply tooltip to provide more precise information on the origin of supply.
Naval AI
- Generic taskforces and standby fleet homebase selection have been updated to be more sensible.
- Added logic to prevent the AI from over-assigning patrols to support naval invasions.
- Convoy Raider:Convoy raiders will no longer join or reinforce combat unless enemy convoys are present.
ItalyExtensive rework of Italian naval equipment for better historical or gameplay accuracy.
Winter WarfareSnow attack penalty is now visible on the move-arrow tooltip for better tactical planning.Hidden→Visible

subjects affected (8)

tap to see balance history

Lend Lease1 Supply System2 Naval AI5 England1 Italy2 USA1 Army AI1 Winter Warfare2

How did this patch land?

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official notes

Hearts of Iron IV · May 13, 2026

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