To see Fixed Maturity Contract specifications, please visit the other page here.
These contracts are listed on the Crypto Facilities MTF.
Perpetual Futures are a type of Futures contract that have no expiration date and have an autorolling feature every 4 hours. These contracts feature a funding rate, which is a usertouser payment designed to keep the price of the perpetual futures contract aligned to its underlying asset’s index price (i.e. the spot price of the underlying asset). If the premium is above zero, then the long positions payout to short positions, and if the premium is below zero, then the short positions pay out to the long positions. Therefore, traders will either pay or receive funding depending on the market movements. The price divergence is calculated every 4 hours and payments are done periodically.
Below is a detailed table of characteristics of the contract and its unique funding rate, followed by multiple examples to demonstrate the mechanics of the contract. All singlecollateral inverse futures use individualised margin wallets for the contract's respective underlying asset. For singlecollateral inverse futures, profit/loss and funding are realised in the base currency.
Symbol  Status  Base Currency  Quote Currency  Contract Size & Minimum Order  Tick Size  Price quotation  Max Position Size  Impact Mid 
Maximum Leverage 

PI_XBTUSD*  Active  Bitcoin (BTC)  U.S. Dollar (USD)  1 USD  0.5  USD per 1 BTC  75,000,000 USD  1,000 USD  50x 
PI_ETHUSD  Active  Ethereum (ETH)  U.S. Dollar (USD)  1 USD  0.1  USD per 1 ETH  45,000,000 USD  1,000 USD  50x 
PI_LTCUSD  Active  Litecoin (LTC)  U.S. Dollar (USD)  1 USD  0.01  USD per 1 LTC  6,000,000 USD  1,000 USD  50x 
PI_BCHUSD  Active  Bitcoin Cash (BCH)  U.S. Dollar (USD)  1 USD  0.1  USD per 1 BCH  10,000,000 USD  1,000 USD  25x 
PI_XRPUSD  Active  Ripple (XRP)  U.S. Dollar (USD)  1 USD  0.0001  USD per 1 XRP  3,000,000 USD  1,000 USD  10x 
*BTC is used on the platform UI. XBT is used on the API and account logs. Both refer to Bitcoin (BTC).
Additional Information  

PnL Settlement Method  Inverse futures are cashsettled in base currency 
AutoRoll Period  Every 4Hours on 12 UTC, 16 UTC, 20 UTC, 24 UTC, 4 UTC, 8 UTC 
Ratesetting Calculation Window  Rate for next period is calculated over current 4hour period (e.g., rate for 1216 UTC period is calculated in window between 812 UTC) 
Funding Rate 
Between start and end of Ratesetting Period the Funding Rate is computed as the timeweighted average premium, and standardised to a perhour basis. Permissible range per 1 hours: [0.1%, +0.1%] (i.e., 80 basis point magnitude for 8hour realisation period) 
Payout Frequency 
Continuously based on Funding Rate set at the end of the prior Funding Period. Positions will immediately and continuously receive or send funding while open in the perpetual contracts. The funding accumulates as UPL and settles every 4 hours at end of Funding Period, or when user changes net open position (whichever occurs first). 
Funding Rate Multiplier 
n = 8 This is the coefficient used in the calculation of the funding rate. A value of 1/n means that, ceteris paribus, it will take n hours to realise the Average Premium. Example: if the Average Premium is 0.32% for the 4hour period, then Funding Rate is equal to 0.04%, meaning that over the course of 8 hours, this 0.32% total will be realised. 
Funding Rate Calculation 
In a given 4hour Funding Period, Premium values calculated from minutely perpetual contract prices (240 observations) using an Impact Mid are recorded versus the Real Time Platform Ticker. The Impact Mid is the median of the average entry price marketselling x value of contracts and marketbuying x value of contracts. See table above for contractspecific values. The Average Premium is calculated as the average of the mid 120 values recorded from the above 240 observations. Finally, this value is weighted by the Funding Rate Multiplier. If Average Premium is greater than 0 for the 4 hour period, those in Long positions will continuously pay out to Short positions, which pushes the price closer to Index. If Average Premium is less than 0 for the 4 hour period, those in Short positions will continuously pay out to Long positions, which pushes the price closer to Index. 
Trading Hours  24 hours/day, 7 days/week, 365 days/year (excluding maintenance) 
Fee Structure 
Kraken Futures uses a makertaker fee structure. Fees are calculated as a percentage of the notional order value for a matched trade. No fees are charged on autoroll or funding payouts  these occur strictly between counterparties. 
Contract Expiration 
The perpetual futures are nonexpiring, which means that positions in the contract are never “expired” or “matured”, however there is a settlement process every hour that applies funding to anchor the spot value to the Index. See Last Trading for more information. 
Settlement time 
Every 4 Hours on 12 UTC, 16 UTC, 20 UTC, 24 UTC, 4 UTC, 8 UTC: The accumulated unrealised funding is settled and new rate set based on TWAP premium to index in prior rate period. 
Last Trading 
This contract remains trading perpetually and would only expire in an emergency situation if the market venue deems necessary to settle/expire the contract. This would only occur in exigent circumstances if the Market Risk Committee deemed it necessary to facilitate a fair and orderly market. The market venue reserves the right to set the contract to postonly, suspended, or settle the contract at any time and without warning due to either adverse market conditions or regulatory risk. 
First Trading  August 31, 2018 
Initial Margin  As low as 2% 
Maintenance Margin  Half of Initial Margin 
Maximum Initial Leverage  Up to 50x 
Mark Price 
Mid Price of Order Book bounded by a range defined by index with antimanipulation coefficient. The Mark Price is calculated using the impact mid price and is bound to the underlying index price. The premium for perpetual contracts is capped at 1%. Note: in the extremely rare circumstance that the Index Price is unavailable for whatever reason, the above caps may not apply and the Mark Price will be equal to the Impact Mid Price. 
Margin & Settlement Currency  Base currency (e.g. PI_ETHUSD realises PnL in ETH) 
Note on Funding Rate
The funding rate for a given perpetual contract is represented in two different ways:
 absolute rate: The amount of funding an account will receive by maintaining a 1 contract unit short position for 1 hour. This is more useful for account log purposes.

absolute funding payout = # of contracts * absolute funding rate * time elapsed within funding period without position alteration

 relative rate: The absolute funding rate relative to the spot price at the time of funding rate calculation. This is an intermediate value in the calculation of the absolute funding rate and is the number we display in the front end (as a %) as the 'funding rate'.

relative funding payout = # of contracts * (relative funding rate/spot price) * time elapsed within funding period without position alteration

Examples
In order to get a complete understanding of the rate dynamics of the Perpetual Contract, we present examples to demonstrate the key features. Click the example titles below to expand:
Example Funding Rate 1: (8hour rate realisation length)
Assume time is 12 UTC and that price of BTC is $7,000 (via realtime index) and the Perpetual trades at $7,010 the whole time until 16 UTC. The average premium is computed as 0.1428% for the 4hour period ($10/$7,000). This leads to a funding rate of 0.1428 / 8 = 0.01785% per hour.
Now assume that you are in a short position of 100,000 Contracts. If you hold this position from 16 to 24 UTC and the premium in 1620 UTC period remains as 0.1428%, then you will earn interest of $142 for the eighthour period ($100,000*0.001428) in BTC terms, so $142/$7,000 = 0.0204 BTC.
Example Funding Rate 2: (Maximum rate)
Assume time is 12 UTC and that price of BTC is $7,000 and the Perpetual trades at $7,100 until 16 UTC. The average premium is computed as 1.428% for the 4hour period. This leads to a funding rate of 1.428 / 8 = 0.1785% per hour.
The maximum funding rate per hour in any given period is 0.1%. The minimum is 0.1%.
As a result. this 0.1785% hourly rate is floored to 0.1% per hour, so that the maximum 8hour realisation will not exceed 0.80%.
Note that there is no "dampening" of rates done in this model: if a fourhour computed rate is near 0, then it will stay pay out non0 value even if it is de minimis.
Example Funding Rate 3: (Absolute vs. relative rate)
Assume time is 12 UTC and that the realtime index price of BTCUSD is $7,000 and the relative rate set for the fourhour period is 0.05% per hour.
Now assume the time is 14 UTC and the Perpetual trades at $8,000 and you enter a Short position of 125,000 contracts at this price.
You will immediately begin receiving funding at an absolute rate of 0.05%/$7,000 = 0.000007142% per hour per contract unit.
In your account log you will then see this rate applying in your unrealised PnL through continuous funding payout equal to:
 0.00000007142 * 125,000 = 0.008928 BTC per hour
 0.00000248 BTC per second
This will pay out continuously until 16 UTC where the relative funding rate will change based on the market activity between 1216 UTC.
Assume this new relative funding rate is now 0.03% and the realtime spot index is $7,900 for BTCUSD at 16 UTC.
In your 125,000 Contract short position at the end of the 2 hour period you will have 0.017856 BTC applied in your account log at 16 UTC.
From 16 UTC to 20 UTC a new absolute funding rate will begin applying of 0.03%/$7,900=0.000003797% per hour per contract unit.
Example Funding Rate 4: (Variable interperiod rate)
Assume time is 14 UTC and you enter a position long 200,000 Contracts on BTCUSD at $7,000. Assume that the funding rate for the fourhour period (1216 UTC) is set as 0.04% per hour.
At 16 UTC, after you have held this position for two full hours, you will have earned $80 per hour (0.0004*$200,000). This is $80*2=$160 USD equivalent or $160/$7,000 = 0.0228 BTC, which credits continuously throughout the two hour period you hold it.
However, during this period , the price was at a premium and so the new fourhour rate set for 16  20 UTC is 0.04% per hour. After two hours of holding the position, you have paid 0.0228 BTC and you close at 18 UTC, two hours later.
Your funding for the four hour period you held the position is thus 0.0228 BTC for the last two hours of first period then 0.0228 BTC for the first two hours of the second period and your net flows are 0 for this.
Example Funding Rate 5: (Fixed intraperiod rate)
Assume time is 14 UTC and you enter a position long 500,000 Contracts on BTCUSD with realtime index at $7,000. Assume that the funding rate for the fourhour period (1216 UTC) is set as 0.033% per hour.
At 16 UTC, after you have held this position for two full hours, you will have paid $165 per hour (500,000*0.00033). For two hours this costs $165*2=$330 USD equivalent or $330/$7,000 = 0.04714 BTC, which debits from your position continuously throughout the two hour period you hold it, in the form of Unrealised Profit/Loss (UPL).
Example Funding Rate 6: (Booking of unrealised funding)
Assume it's 12 UTC you are in a 250,000 Contract long position on BTCUSD with realtime index at $7,000 and the rate in the funding period is 0.05%. This earns you funding of:
 0.0005 * 250,000 = $125
 $125/$7,000=0.01785 BTC per hour
 0.0002976 BTC per minute
 0.00000496 BTC per second
 0.00000000496 BTC per millisecond
This credits and debits every millisecond to every user with an open position. It credits first as "UPL" which is "unrealised" profit and loss, but you have the funds available right away to use in further positions or transfer into your Cash account.
The funding accumulates as UPL and is booked into your account log and realised when one of the following events occur:
1. You adjust your open position up or down by any amount
2. You hold until the end of the Funding Period, at which point it is booked (occurs every four hours)
*XBTUSD is used for logs download and Futures API only
The decimal and thousands separators shown in this article may differ from the formats displayed on our trading platforms. Review our article on how we use points and commas for more information.