Basic Supply Rules for Newbies

[Taxman66]

Because I was asked this in a PM, I thought I would shoot a post here to cover the critical basics of the supply rules:

HQs
A lone HQ (at full strength) receiving 6+ intrinsic (i.e. map resource) will distribute (provide) 10.
A lone HQ (at full strength) receiving 5 intrinsic will distribute 8.
3 or 4 intrinsic will distribute 6. That means at this level the HQ will not provide enough to fully reinforce anything around it.
1 or 2 intrinsic will distribute 5.
Less than that is even worse bad news.

Damaged HQs also provide less supply.

Chain HQs:
A HQ may be supplied from another HQ. This is called chaining.
A chained HQ receiving 1 or more supply from another HQ (itself receiving an intrinsic 3 or more) will distribute 8.
A chain only exists with 1 link, i.e. 1 HQ supplier and 1 HQ receiver.
There can be multiple chains in an area, but each will be 1 link so a 2nd chain requires 2 more HQs (HQ 1 supplies HQ 2; HQ 3 supplies HQ 4).
I believe any HQ (minor/allied/major) on a side can support another on the same side, with the exception of Russia and Western Allies (iirc).
THE COMPUTER/GAME DETERMINES THESE LINKS, NOT THE PLAYER. THEY ARE NOT GUARANTEED TO FLOW THE WAY YOU WOULD PREFER.
Generally the computer will choose the better intrinsic supplied HQ (particularly if it is getting 5+) to supply the HQ getting less than 5 intrinsic. HOWEVER, the computer also prefers to have the lower valued (HQ quality) HQ supply the better (HQ quality) HQ. e.g. the computer will prefer to have Gort support Monty and not the other way around.

Land Units
Land units can be supplied from any HQ (or intrinsic), with some exceptions (Western Allies in Russia).

Air Units
Air units can only be supplied from a HQ if they are linked to a HQ (though not necessary the same one), or by intrinsic supply. It is very important to remember this and keep air units linked to a HQ if not near a high intrinsic source. If you operate air units, be sure to check and possibly change which units nearby HQ(s) are linked the following turn. You might also want to consider unlinking some units to the HQ (on the turn the air units operate) so that the HQ has free slots to automatically link the operated air units at the start of the next turn.

Land and Air Units
Upgrading and Reinforcement
With 6+ supply units can be upgraded and fully reinforced.
With 5 supply units can be upgraded and reinforced to str 8.
I think it goes 4->str 7; 3->str 6; and so on.
I'm not 100% sure about reinforcing/upgrading HQs, if chained HQs can do so or if it based solely on intrinsic

Morale and Readiness
Units with higher supply recover morale & readiness better. Units supported by a HQ get an additional bonus to recovering morale & readiness.
Units that don't move/do anything also recover better.
Operating units and Force marching units costs morale/readiness (and shells for forced marched arty iirc). Don't be afraid of this as they can recover it pretty quickly. i.e. GE units will and should force march from Poland to West Germany in order to attack timely. On the other hand it is preferable not to force march (a bit less so for operating) right into the front line.
Swapping units costs some morale/readiness; but often allows additional attacks and allows the swapped in unit to keep some/most of the entrenchment of the original unit. A unit that just swaps doesn't count as having moved so it can be reinforced or upgraded.

[Taxman66]

Chain HQ example

The HQ in El Alamein is distributing 8.
The HQ west of Sidi Barrani is getting 2 from Sidi (and 4 or less from Bardia).
The Western HQ would distribute 5 (Sidi) or 6 (if Bardia was at 4 or 5, meaning the HQ was getting 3 or 4 from that town).
However, the HQ in El Alamein is distributing 8 and the Western HQ is getting 1 from the El Alamein HQ. Thus the Western HQ is supported by the El Alamein HQ (Note that there is no other link possible so this one is guaranteed to be established). Thus the Western HQ also distributes 8.

[Elessar2]

I believe the implication of your screenie is that the max link distance is 7, if the boosting HQ is at 8 supply, 9 if it is at 10.

[Taxman66]

Yes, as the receiving HQ must get 1 supply from the supplying HQ.

[cfera]

Thank you so much for explaining this. I was used to the old supply rules and was completely confused during the ongoing tournament!

[Duedman]

Very good summary. It took me like 30 matches to realize that HQs supplied by another HQ DO NOT use the same values as "single" HQs (i.e. you need 5 supply for an 8)
Once you know that (and the necessity for 3 base supply for an HQ to boost at all) certain situations become a lot more clear / easier.
For example you can quite easily keep the Africa Korps well supplied if you position the boosting HQ in a way, that it gets its 3 supply from as many different sources as possible.
Not beeing able to actively choose who boosts whom is a constant nuisance tho.
I have quite a few screenshots of super stupid situations that can cost the whole match. But since I made my point clear already in another topic I did not post them

On the other hand it is preferable not to force march (a bit less so for operating) right into the front line.

On some occasions it can be preferable to forcemarch to the frontline and even behind it.
You can pull off really mean encirclements that way. If there is a gap in the frontline which you can not reach due to Zone of Control - have a para jump in there and use his 1 move to go even further behind the lines capturing 1 or more empty neighboring hexes.
Then forcemarch your zergs...errr russian mobility corps to build a continuous line of units. Repeat that from the other flank. Yes, forchemarched units with very low supply are fragile. But encircled units with supply of 0 wont hurt them.

[OxfordGuy3]

"Air units can only be supplied from a HQ they are supported by (or intrinsic)" - I'm not sure that is actually true, I think as long as an air unit is attached to any HQ, it can benefit from the supply pushed by a different HQ (in 1.24) - I've noticed this in Egypt, as my German aircraft (attached to Rommel) seem to be able to get 6 or 7 supply if within 2 hexes of an Italian HQ (but much further away from Rommel).

[Taxman66]

You're right.
I wonder if that changed at some point.

I'll edit the above post later today

[OxfordGuy3]

I think it was changed to receive supply from any HQ of a compatible ally as long as attached to an HQ in a later patch to when they first brought in the air attachment supply rules. This helps a bit for the Axis in Africa, as they can have Rommel nearer the front with an Italian HQ providing supply to all Axis air units (as long as the German ones are within attachment range of Rommel). It also means less micromanagement.