Skyrim:Speech

The Speech skill (referred to as Speechcraft in the Console) allows you to more effectively persuade people and to barter with shopkeepers. Perks in this skill allow you to get better deals when trading, buy and sell any kind of item to any merchant, and make it more likely for a persuasion or intimidation attempt to succeed. The Speech skill tree has a total of 9 perks, requiring a total of 13 perk points to fill.

In-game Description: The skill of persuasion can be used to get better prices from merchants, and persuade others to do as you ask.     

Skill Perks
 
 
 

 
 
 

Skill Usage
Your Speech skill determines the chance of successfully being able to get information out of an NPC using intimidation or persuasion. These Speech Challenges will be provided as options during certain dialogues.

Special dialogue options include:
 : influence someone by reasoning with them. Chances of success depend solely upon your Speech skill.
 : influence someone by threatening them. Chances of success depend upon your Speech skill and your level subtracted by the NPC's level. For example, a 50 difficulty Intimidation check will succeed with a Speech skill of 45 if your character is at least 5 levels higher.
 : influence someone by giving them money. Factors influencing chance of success are unknown.

Your Speech skill also affects merchant prices; prices can be further improved using some of the Speech skill perks, barter potions or enchanted equipment.

The base rate for buying/selling is based solely on your Speech skill and any perks or Fortify Barter effects are applied to prices afterwards.

Bribe Formula

 NPC Morality  = (NPC Morality Actor Value * fBribeMoralityMult) + 1.0
 v11 = ((NPC Actor Level * fBribeNPCLevelMult) + Player Level) - (((Player Speech Actor Value - NPC Speech Actor Value)) - 100.0) * fBribeSpeechCraftMult)
 bribeValue = (v11 ^ fBribeCostCurve) * (fBribeScale * NPC Morality)


Persuasion Options
What follows is a list of all persuasion attempts that can be made in Skyrim. Spoilers in this list are intentionally kept very minor. All speech challenges fall into one of five categories: Very Easy, Easy, Average, Hard, and Very Hard. Their skill requirements to pass are 10, 25, 50, 75, and 100, respectively. Possessing the Persuasion perk reduces the requirements on all but Very Easy challenges by 30%, dropping them to 10, 18, 35, 53, and 70, respectively. Wearing the Amulet of Articulation allows you to succeed at any persuasion check in the game regardless of skill.

Impossible to Fail
Persuading Loreius to help Cicero during Delayed Burial.
Getting Lod to pay you 25 gold before searching for the dog during A Daedra's Best Friend.

(10)
Persuading a shakedown bandit to leave you alone for 50 gold.
During The Forsworn Conspiracy, getting Margret to reveal information.
Getting a free sample from the attendant at Redwater Den. 

(25/18)
 

 
 

 
 

 

(50/35)
 

 
 

 
 

 
 

 
(75/53)
 

 
 

 
 

 

(100/70)
Convincing Faralda to let you join the College of Winterhold without taking a test.

 

Prices
Prices are computed by the following:

The Base Price Factor is calculated by your skill level; each skill rank reduces the price factor by .013 by default, and skill levels over 100 have no effect:

 price factor = fBarterMax - (fBarterMax - fBarterMin) * min(skill,100)/100
 price factor = 3.3 - 1.3*min(skill,100)/100
 price factor = 3.3 - .013*min(skill,100)

fBarterMax default is 3.3, fBarterMin default is 2.0 (defines a  base vendor-selling-range of 200% to 330% of an item's base value, and a vendor-buying-range of 30% to 50%).
the function min(x,y) return the smallest of two or more arguments (here, [skill-level] or [100]).

The modified Price Factor depends on perks and Fortify Barter bonus:

 sell price modifier = HagglingS * AllureS * (1 + Fortify Barter from potion) * (1 + the sum of Fortify Barter from equipment + Fortify Barter from Blessing of Zenithar)
 buy price modifier = HagglingB * AllureB * (1 - Fortify Barter from potion) * (1 - the sum of Fortify Barter from equipment - Fortify Barter from Blessing of Zenithar)

The final price combines the two Price Factors and rounds to the nearest whole number:

 sell price = round(value of item * sell price modifier / base price factor)
 buy price = round(value of item * buy price modifier * base price factor)

HagglingS = 1.10 at Rank 1, 1.15 at Rank 2, 1.20 at Rank 3, 1.25 at Rank 4, 1.30 at Rank 5. AllureS = 1.10

HagglingB = 0.91 at Rank 1, 0.87 at Rank 2, 0.83 at Rank 3, 0.80 at Rank 4, 0.77 at Rank 5. AllureB = 0.91

:Buying multipliers are the reciprocal of the respective selling multiplier, but rounded to two decimal places (a percentile). Do not use unrounded (untruncated) values, as it will yield incorrect results. (For example, at rank 2, HagglingB is 0.87.  1/1.15 is actually slightly less than 0.87, so using the full (untruncated) value may get you a lower-than-actual buying multiplier.)

At 0 skill and no perks, the final price factor is 3.3 for buying and 0.303 for selling.
At 15 skill and no perks, the final price factor is 3.10   for buying and 0.322 for selling.
At 100 skill and no perks, the final price factor is 2 for buying and 0.5 for selling.
At 100 skill and all haggling perks, the final price factor is 1.54 for buying and 0.65 for selling.
At 100 skill and all perks, including Allure, the final price factor is 1.4014 for buying and 0.715 for selling.
Trade price cap: (max sell price = value * 1.00), (min buy price = value * 1.05).

Skill levels over 100 have no effect.

Investor
Investing 500 gold into a business with the Investor perk immediately increases their current gold by 500. Investing is as simple as speaking to a merchant NPC and selecting the 'I want to invest in your business' option. This can only be done at the same time of day as they would normally allow sales.

All merchants who are available for investments are identified in the notes column on the Merchants article.

Skill Increases
Character Creation
The following races have an initial skill bonus to Speech:
+5 bonus: Breton, Nord

Trainers
Dro'marash with the Khajiit Caravans (Common)
Revyn Sadri in Windhelm (Common)
Ronthil  in Volkihar Keep (Expert)
Ogmund in Markarth (Expert)
Giraud Gemane of the Bards College in Solitude (Master)

Skill Books
2920, Second Seed, v5
A Dance in Fire, v6
A Dance in Fire, v7
Biography of the Wolf Queen
The Buying Game

Free Skill Boosts
+1 Speech reward (as well as +1 to all other Stealth skills) from Inge Six Fingers (Bards College) for completing the quest Finn's Lute.
+1 Speech reward from Malur Seloth (Winterhold) for completing the quest Some Light Theft
+1 Speech reward from Ysolda (Whiterun) for completing the quest Rare Gifts
+2 Speech reward from Azzadal for jumping off of Bard's Leap Summit. Jump from opposite the Word Wall in Lost Valley Redoubt off the bridge that extends over the waterfall for Azzadal to appear.
+5 Speech reward (as well as +5 to all other stealth skills) by selecting "The Path of Shadow" from the Oghma Infinium after completing the quest Discerning the Transmundane.

Gaining Skill XP
Trading with merchants will increase the Speech skill. The amount of skill progress gained is based on the base value of the item being bought/sold and is not limited by the merchant's available gold. However, if you trade multiple units of an item in one transaction, you will only gain experience equivalent to trading a single unit; for optimal leveling, sell each item one at a time, and sell expensive items.
Fortify Speech and Barter allow for more items to be purchased for a given amount of gold, which increases skill gains.
Successful Persuade, Intimidate, and Bribe attempts in conversations will also increase the skill.
Barter with skill trainers that sell items (trainer-merchants). At higher levels (51 and up) buying 5 training sessions from a trainer-merchant will cost a minimum of 8,200 gold. This will temporarily buff the amount of gold that the trainer-merchant has on hand by the amount of gold used for training sessions. Then you can sell items to the trainer-merchant. At the highest levels you can trade 28,000 worth of items in a single visit if you have saved a level up prior to training (this allows 5 training sessions, a level up, then another immediate 5 sessions). This can require a lot of gold on hand and you should avoid allowing the trainer-merchant to accumulate more than 32,767 gold due to a bug with merchant banks.
One method for those who have a very large amount of money is to don your best haggling apparel (e.g. Guild Master's Hood and a Necklace of Haggling), go to the local fence and sell/rebuy your most expensive weapons (e.g. a pair of Legendary Blades of Woe) repeatedly until your skill increases to the desired level.  As you will lose money (the amount varies based on perks and equipment) with every sell/buy cycle, the merchant will end up with a vast quantity of gold if you continue the exercise for long enough. At this point you can sell all your more expensive items (i.e. those items which will normally cost the merchant most of their gold) as well as any others to the merchant until they are back down to 0 gold, or you have run out of items to sell.
One way to train this skill without spending money is to commit a crime with a very low bounty, such as trying to pick a lock one time or stealing an item with a value of less than 10 gold. When your bounty is 5 gold or less, guards may ignore such crimes unless you speak to them. In dialogue, you may get a Persuasion option for the guard to overlook your crime. If you fail the persuasion check with such a low bounty, the guard may ignore the crime anyway. By speaking with and persuading every guard you encounter (except the one who witnessed the crime), your Speech will go from 50 to 100 in 10-15 visits to the town. A bounty of 10 gold may be too high to use this technique. Take note, however: this requires at least 53 Speech (with the Persuade perk) to work; alternately, if you have the gold to spare, you can bribe the guards repeatedly for the same benefit.  
The Fortify Restoration or Fortify Alchemy/Enchanting exploit can be used to acquire items of extremely high value, which when sold will grant immense boosts to the Speech skill.
Speech is one of two skills which has a different Console ID than the name, the other being Archery. The actual Console ID for Speech is  . For example, the Console code for improving Speech is  AdvancePCskill Speechcraft   .
Another way to improve this skill is to repeatedly persuade Calcelmo during the completion of the Buy Dwarven Artifact quest, by exiting the dialogue after the persuasion and before deciding whether to accept his offer. Note that this requires a certain level of Speech in order to work.