Skyrim - Staves

Staves are one-handed weapons that cast a spell from their own charge instead of your Magicka, so anyone can use one whatever their magic skills are. That is the whole appeal: a warrior with 15 Destruction can carry a Staff of Fireballs and throw 40 point explosions with it. The catch is that a staff never gets better, never raises a skill, and stops working entirely when the charge runs out.

There are 44 standard staves across the five schools. What separates them is not damage, it is casts per charge, a figure no menu in the game shows you: divide the staff's charge pool by its cost per cast and the answers run from 500 down to 3.

Combat

Where it wins

Skill does not gate the effect. A Staff of Incineration does its 60 points of fire damage at Destruction 15 exactly as it does at 100, which no spell can claim.
It costs no Magicka, so a staff in the off hand is free damage next to a sword, a shield or a second staff. Staves are one-handed in Skyrim and can be dual wielded.
Destruction perks still apply. Augmented Flames takes a Staff of Flames from 8 damage per second to 10, so a caster gains from a staff as well.
The cheap Illusion and Restoration staves are effectively unlimited. Staff of Courage costs 1 point per cast against a 500 charge, which is 500 casts before it needs a soul gem.

Where it loses

Using a staff raises no skill. Hours with one leave Destruction exactly where it started, which makes staves a poor choice for a character still levelling.
Higher skill does not raise the damage, only the charge cost. The staff you find at level 10 is the same staff at level 50.
The expensive ones run dry fast. Staff of Fear gets 3 casts from a full charge and Staff of Paralysis 6, so both need a filled soul gem after almost every fight.
Blacksmiths will not buy or sell them, staves cannot be disenchanted, and the Soul Siphon perk does not recharge them.

Builds

A staff is at its best on a character who is not a mage. The effect ignores your skill, so the value is highest where the skill is lowest: a two-handed warrior gains a ranged option, a stealth archer gains a panic button, and neither has to spend a perk.

For a warrior: a Destruction staff in the off hand with a one-handed weapon. Staff of Firebolts at 24 casts is the sensible middle, and Staff of Thunderbolts at 58 casts is the outlier worth hunting.
For a mage: staves cover the school you did not perk into. A Destruction specialist carries Staff of Revenants for a free tank rather than spending points in Conjuration.
For a low level character: Illusion staves punch above the level they drop at, because crowd control does not scale with your skill either. Staff of Fury turns a group against itself at level 1.
Where the next chunk of value comes from: not a stronger staff, a cheaper one. Casts per charge varies by more than a hundredfold across the set while damage varies by eight, so the upgrade that matters is finding the same effect at a lower cost per cast.

School	Staves	Most Casts	Most Valuable
Alteration	2	Magelight, 71	Paralysis, 3965
Conjuration	12	Revenants, 27	Daedric Command, 2307
Destruction	15	Thunderbolts, 58	Icy Spear, 2931
Illusion	8	Courage, 500	Fear, 2443
Restoration	7	Healing Hand, 111	Grand Turning, 1520

Best Staves

Staff	School	Casts	Value	Level	Why Take It
Staff of Thunderbolts	Destruction	58	778	34	The best value in the game, by accident. It ships with the apprentice Lightning Bolts enchantment rather than the expert Thunderbolts one, so it costs 51 per cast instead of the ~300 its tier implies. That is 58 casts of 25 shock damage against Chain Lightning's 12 casts of 40, and it is worth a quarter as much to buy.
Staff of Incineration	Destruction	10	2750	34	Highest single-hit damage of any staff at 60 points of fire, and fire also burns for extra damage afterwards. Ten casts is thin, so this is the one you save for a boss rather than trash.
Staff of Fireballs	Destruction	15	1309	22	40 points in a 15 foot radius, which is the only staff answer to a group. Available a full tier earlier than Incineration at level 22.
Staff of Revenants	Conjuration	27	824	22	Most casts of any Conjuration staff by a wide margin, and it raises a powerful corpse rather than a weak one. A free tank on a 27 cast budget, for a character who never spent a perk on Conjuration.
Staff of Courage	Illusion	500	79	1	500 casts, 79 gold, available from level 1. It costs 1 point per use against a 500 charge, the cheapest cast in the game, and the extra health it gives a follower makes it a permanent buff you never have to recharge.
Staff of the Healing Hand	Restoration	111	198	10	Heals a follower 4 points per second at 9 charge per cast. The only sustainable way to keep a companion alive without perking Restoration yourself.
Staff of Paralysis	Alteration	6	3965	34	The strongest effect on this list and the most expensive item, at 3,965 gold. Ten seconds of paralysis ends most fights outright, but 6 casts per charge means one soul gem per encounter.

Notes

Casts per charge is the stat that matters, and it is charge divided by cost per cast. The range is enormous: Staff of Courage gets 500, Staff of Fear gets 3.
A discharged staff is inert until recharged with a filled soul gem, the same as any enchanted weapon. The Soul Siphon perk is the exception that does not work on staves.
Staves cannot be disenchanted, so they never teach you an effect.
The named effect is not always the spell. Staff of Thunderbolts carries Lightning Bolt, not Thunderbolt, which is why its numbers look wrong next to the rest of its tier.
Only spell merchants and general goods merchants trade staves. A blacksmith will not touch one.
Unenchanted staves added by Dragonborn can be enchanted at the Staff Enchanter in Tel Mithryn, but the staff type fixes which school you may put on it.
In Morrowind and Oblivion a staff took both hands. In Skyrim it takes one, which is what makes the off-hand staff build possible.