Support Companies technology

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Support Companies technology unlocks and enhance support battalions.

Support Equipment[edit]

Support Equipment
1Aluminum 2Steel
Support Equipment.png

Radios, Jeeps, Pontoons & other equipment used to support troops.


Production Cost:

The 1918 available technology Support Equipment is the basis for the research of all support battalions. It enables the equipment of the same name, which is needed for all support battalions.


Unit 1936 (base) 1939 1942 1945
Engineers +5 Entrenchment
Terrain bonuses
+2[1] Entrenchment
+10% Attack and Defense on forts
+2[1] Entrenchment
+10% Attack and Defense on rivers
+2[1] Entrenchment
+10% Attack and Defense on urban
Recon +1 Reconnaissance
+10% Speed apart from urban and desert.
+2 Reconnaissance +2 Reconnaissance +2 Reconnaissance
Military Police +20% Suppression Bonus +10% Suppression Bonus +10% Suppression Bonus +10% Suppression Bonus
Maintenance +25% Reliability +5% Reliability +5% Reliability +5% Reliability
Field Hospital +20% Trickleback
−10% XP loss
+10% Trickleback
−10% XP loss
+10% Trickleback
−10% XP loss
+10% Trickleback
−10% XP loss
Logistics −10% Supply Usage −10% Supply Usage −10% Supply Usage −10% Supply Usage
Signal +20% Initiative +12% Initiative +12% Initiative +12% Initiative

Note that percentage bonuses are multiplied, not added. So, a base stat of 80%, with a 20% bonus, is 96% (80 * 1.2), not 100%.

Support Companies In-Depth[edit]

Anti-Air (AA): AA will primarily help protect against tactical bombers and CAS attacking a battle that the division is participating in, allowing multiple divisions in the same battle to pool their AA fire. Towed and self-propelled Anti-Air will only fire at enemy planes attacking that division or other divisions that take part in the same battle.

  • They do nothing against strategic bombers (they fly too high), so adding AA to garrisons will not help protect industry.
  • At least as of version 1.3, the Devs have reported that attached AA can shoot down fighters, but it takes a lot of it (the example in the video showed multiple line battalions, not just a lone support company). Of course, if you have no fighters, putting AA in every division on the front line may be your only option.
    • Editor's Note: The video where the Devs said they can shoot down fighters is the "Together for Victory feature stream" on Youtube.
  • It should be noted that towed AA units also have half-decent anti-armor capability. For example, the tier 2 towed AA has enough Piercing to negate the Armor value of tier 1 medium tanks. However, self-propelled AA doesn't have anywhere near as much anti-armor capability.
  • Having towed or self-propelled AA in a division reduces the malus that enemy air superiority provides.

Engineers (ENG): Engineers provide a movement bonus in forest, jungle, marsh, and rivers. They provide a constant defense bonus in forest, jungle, hills, marsh, rivers, and forts. They also provide an entrenchment bonus on top of that. Upgrading engineers increases the entrenchment bonus. Lastly, they provide a constant attack bonus to amphibious (naval invasions), which does stack with Marines.

Reconnaissance (REC): A recon company provides a speed bonus on most terrain and a reconnaissance points bonus to commander skill that increases the chance to counter the tactic chosen by the enemy for a day of combat.

  • They provide a 10% speed boost on all terrain except marsh, desert, and urban. In marsh they provide a 5% speed bonus. 0% in desert and urban. This speed bonus does not increase with upgrades. Consider the value of increasing the infantry speed from 4 km/h to 4.4 km/h, or motorized/light tanks from 12 km/h to 13.2 km/h, and consider how this may combine with vehicle variants to achieve specific speed targets to outpace or overrun enemy. The answers will vary from player to player and likely from division to division. For example, exploitation and envelopment divisions may find the extra speed valuable while assault and breakthrough divisions may not, although they may find the combat tactics bonus valuable in intense battles.
  • Recon companies also help counter enemy tactics. Details on exactly how this works are not available. However, reports of battles in progress show the tactic being used by each side for the current day, with a big red 'X' on a tactic if it is countered. In the middle there is a button that will display all of the tactics in the game, with unavailable tactics padlocked. Tactics can give damage, defense, movement speed, and combat width modifiers. If an enemy's tactic is countered, they do not get the benefits. However, it's just a chance to counter, and the calculation of that chance is not known. Each recon upgrade increases reconnaissance points. Factors to consider in evaluating recon companies include the relative range of tactics available to each side, potential importance of tactics to an army's warfighting, and opposing commander skill levels. How exactly reconnaissance points from multiple divisions in a combat are combined and how they interact with commander skill levels is not yet known.

Military Police (MP): This support company is not intended for the front lines, or any combat really. It provides a percentage increase to the division's Suppression statistic. Suppression counters partisans operating in a region, preventing them from damaging industry. Best when combined with cavalry, which have better suppression than infantry battalions. While they can simply be added to a garrison division, most prefer to create a division template specifically for MP's.

Maintenance (MAIN): Maintenance companies increase the Reliability statistic of all equipment in a division, thus significantly reducing the amount of equipment lost due to attrition. Unfortunately the division designer's Reliability stat doesn't seem to work, even with only a single battalion. As a result, all calculations for this company must be done outside the game.

  • The effect is very powerful right from the start, with a 25% bonus. This means that (land) equipment with 80% reliability will get boosted to 100% (80 * 1.25). This allows reliability improvements to equipment that normally cannot be upgraded. Mechanized are the most significant, but also motorized, all of the towed weapons, and support equipment. It benefits infantry equipment too, but infantry equipment is easy to produce and starts at 90% reliability, rather than the usual 80%.
  • For equipment that can be upgraded, such as tanks, it means putting upgrade points into reliability is unnecessary unless it drops below 80% (or as low as 64% to get 80% reliability after the bonus). That can potentially save a lot of XP. Of course, that would require all tanks of that design to have a maintenance company.

Field Hospital (HOS): These provide two bonuses. First, with the 1936 hospital, 20% of the losses in combat get returned to the Manpower pool rather than being lost forever. Second, 10% less XP is lost from combat losses. Upgrading the field hospitals increases both of these bonuses. The more combat a division sees over time, the greater the overall benefit from a field hospital. Conversely, they are a waste in a division unlikely to see sustained combat or likely to be eliminated if engaged in combat, such as some security, garrison, or coastal defense divisions.

  • From the manpower perspective, bigger is better. Each field hospital, being percentage based, will simply save more lives in a large division than in a small one.
  • From an XP perspective, however, each soldier is worth more XP in a smaller division. So, it can be worth adding them to a small number of elite divisions. These could be things like marine or paratroop divisions, etc. Another possibility might be a regular infantry division that has already gained a high experience level on its own. By creating a duplicate template, a field hospital can be added to some divisions but not to otherwise identical ones, to help those high XP divisions keep their XP. The higher a division's XP gets, the more the average will be reduced by casualties (since replacements are always green). Deploying new divisions that have a field hospital while they are still green is a complete waste from the XP perspective. Therefore, you have more incentive to train new divisions up to regular before deployment when using field hospitals.

Logistics (LOG): These provide a flat 10% reduction in supply consumption, which improves with upgrades. Since it's percentage based, they will provide the most benefit in the most supply-hungry divisions. Since artillery uses a lot of supplies, divisions with multiple artillery of any type (line/support/self-propelled) are the first place to look. Just open the division designer and compare the Supply Use stat before and after adding the company, then decide if it's worth it. Most large divisions are potential candidates. For infantry, keep in mind that when fighting in places with high infrastructure, where months of fighting can go by without units running low on supply, a logistics company provides no benefit. Supplies have no cost in HOI4. Creating a separate infantry division template specifically for low-supply areas is an option. Other divisions can use that support slot for more combat-related purposes.

Signal (SIG): Signal companies provide an Initiative stat, which speeds up joining a combat from reserve and planning speed. Used in the right place, these can be great. Given that the base planning speed is 2 % per day, a signal company 1 saves you 4 days to reach the standard 50 % bonus(II:5 days; III: 7 days; IV: 8 days). Whether this bonus expedites preparation of invasions or paradrops is unconfirmed. In general these are most useful for troops in frequent front-line combat, or for reserves in critical positions where rapid reinforcement is needed.


  1. 1.0 1.1 1.2 The engineers technologies gives +2 entrenchment but it’s displayed in the game as +200% entrenchment. See: bug report.