FRM Exam Part II · Central Clearing

Initial Margin and Variation Margin at a CCP

Updated 11 October 2026 · Fact-checked

Variation margin (VM) is paid daily or intraday to settle gains and losses on a position, so current exposure resets to near zero. Initial margin (IM) is collateral held against potential future losses over the margin period of risk if a member defaults. IM is sized to a high confidence level, such as 99% or 99.5%.

Understand Margining: Initial Margin and Variation Margin

A central counterparty (CCP) stands between buyers and sellers. If a clearing member defaults, the CCP must close out that member's positions and still honour its obligations to everyone else. Margin is how the CCP protects itself and the other members before it touches mutualised default resources.

Variation margin covers losses that have already happened. Each day the CCP marks every position to market. Members whose positions lost value pay cash; members whose positions gained value receive it. This stops losses from building up. VM is a transfer of value, not a buffer, so it is normally paid in cash and the CCP does not keep it.

Initial margin covers losses that might happen after the member defaults. Even with VM paid up to the last call, the CCP cannot close out instantly. Between the last VM payment and the end of liquidation, prices keep moving. This window is the margin period of risk (MPOR). For cleared products it is often a few days, such as five days for many OTC derivatives and shorter for liquid futures. IM is the loss quantile over that window, often set at 99% or higher (VaR or expected shortfall).

CCPs build IM with models. Common ones are historical simulation VaR or expected shortfall, and SPAN-style scenario grids for futures. Inputs are position sensitivities, volatility, correlations and the MPOR. A longer MPOR or a higher confidence level raises IM. Portfolio offsets between positions lower it. CCPs often add buffers, liquidity add-ons and concentration charges.

Procyclicality is the problem that margin rises in stressed markets, when liquidity is scarcest. Higher volatility feeds directly into models, so IM jumps and members must post more collateral at the worst time. This can force asset sales and amplify the stress. Tools to dampen it include a stressed-period floor in the lookback window, margin buffers built in calm times and released in stress, and weighting of long-run history. These tools trade lower procyclicality against higher margin in calm periods.

Key formulas to remember

Variation margin call: VM call = MtM(today) − MtM(at last settlement) (paid by the party whose position lost value); Settles realised losses. Sign matters: the loser pays, the gainer receives.
Initial margin (VaR-based): IM = VaR(α, MPOR) of the portfolio's P&L over the margin period of risk; Typically at 99% or higher. It covers loss after default, not past loss.
Square-root-of-time scaling: VaR(MPOR) ≈ VaR(1 day) × √(MPOR in days); Valid only if daily returns are independent and identically distributed with the same volatility. Autocorrelation or fat tails make it approximate.
Parametric VaR for IM: IM = z(α) × σ(daily) × √MPOR × Position value; z(99%) ≈ 2.33. z(99.5%) ≈ 2.58. Zero-mean assumption.
Margin period of risk (components): MPOR = time from last VM payment to default + time to close out and hedge; Longer remargining intervals and slower liquidation both lengthen it.

How to solve Margining: Initial Margin and Variation Margin questions

Use this sequence for any margining question, whether it is conceptual or numerical.

1Identify what is being asked: loss already realised (VM), loss potential after default (IM), the MPOR, or procyclicality.
2If VM: compute the change in mark-to-market since the last settlement and decide who pays and who receives.
3If IM: note the confidence level, the MPOR and the daily volatility or VaR given.
4Scale the one-day risk to the MPOR with √MPOR, and state the assumption this relies on.
5Multiply by the z-score and the position value (or use the supplied VaR), and apply any diversification or add-on given.
6Check the direction: longer MPOR, higher confidence or higher volatility must raise IM.
7For procyclicality questions, name the mechanism (volatility raises IM in stress) and the mitigant (buffer, floor, stressed lookback), then state its cost.
8Re-read the stem for units and the time basis (one-day, 5-day, annual volatility) before choosing.

Quickest way: Fast numerical IM check

When to use it: Use when the stem gives daily volatility, confidence level, MPOR and exposure, and asks for IM.

Memorise z: 1.65 (95%), 2.33 (99%), 2.58 (99.5%).
Compute √MPOR (√5 ≈ 2.236, √10 ≈ 3.162).
Multiply: z × daily σ × √MPOR × exposure.
Eliminate options that are off by the factor of √MPOR or that use the wrong z.
For concept questions, remember: VM = past losses, IM = future losses, MPOR drives IM, and procyclicality means margin rises in stress.

Common mistakes in Margining: Initial Margin and Variation Margin

Treating VM as a buffer against future default losses.
Both are called margin and both are collateral.
Fix: VM settles realised mark-to-market changes. Only IM covers the potential loss during the MPOR.
Using a 1-day horizon for IM when a multi-day MPOR is stated.
Students copy the usual 1-day VaR habit.
Fix: Scale by √MPOR (under i.i.d. returns) before multiplying by z and exposure.
Defining MPOR as only the liquidation time.
It sounds like a closing-out period.
Fix: MPOR runs from the last VM exchange to the end of close-out, including the time to detect default, and the remargining interval.
Saying a higher confidence level lowers IM.
Confusing confidence with comfort.
Fix: A higher confidence level means a larger quantile, so IM rises.
Claiming procyclicality is caused by VM.
VM is also paid more in stress.
Fix: The focus is IM models that react to volatility. VM follows actual price moves and is not a model choice.
Thinking anti-procyclicality tools are free.
They are presented only as benefits.
Fix: Buffers and stressed floors raise IM in calm periods, so members face higher routine costs.

Worked examples

Example 1

A CCP sets IM at 99% confidence over a 5-day MPOR. A member's portfolio is worth USD 80 million with daily return volatility of 1.2%. Assuming normal, i.i.d. returns with zero mean, and z(99%) = 2.33, what is the IM?

Show the solution

Daily volatility in USD: 80 million × 0.012 = USD 0.96 million.
Scale to 5 days: 0.96 × √5 = 0.96 × 2.236 = USD 2.147 million.
Apply z: 2.147 × 2.33 = USD 5.00 million.

Answer: IM ≈ USD 5.0 million.

Example 2

A CCP's IM model uses a 1-year lookback VaR. Volatility doubles during a market shock. Explain the effect on IM and how the CCP could reduce the procyclical impact, and what the trade-off is.

Show the solution

IM is a quantile of simulated or modelled losses, so when volatility doubles the quantile roughly doubles. Members must post much more collateral within days.
Calls for extra collateral arrive when liquidity is tight. Members may sell assets, which pushes prices lower and volatility higher.
Mitigants: include a stressed period in the lookback, set an IM floor based on long-run volatility, or build a margin buffer in calm times that can be drawn down in stress.
Trade-off: these tools raise IM in normal times, so members pay more for clearing routinely.

Answer: IM roughly doubles with volatility, creating a procyclical liquidity drain. Stressed-period floors and buffers dampen the jump but raise IM in calm markets.

Exam tips

Keep the pair straight: VM = realised past loss, IM = potential future loss over the MPOR.
In numerical questions, check whether the MPOR is given in days and scale by the square root, not by the number of days.
When a stem says 'procyclicality', answer with the mechanism, the tool and the trade-off.
Expect direction questions: longer MPOR, higher confidence, higher volatility and less netting all raise IM.
Note that CCP margin is calculated on the clearing member's portfolio, so offsets reduce IM.

Practice questions from Central Clearing

Margining: Initial Margin and Variation Margin in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Margining: Initial Margin and Variation Margin: frequently asked questions

What is the difference between initial margin and variation margin?

Variation margin settles gains and losses already incurred, usually in cash each day. Initial margin is a collateral buffer held against possible losses after a default, during the margin period of risk.

What is the margin period of risk?

It is the time between the last variation margin exchange with the defaulting member and the point where its position is closed out or hedged. Prices can move in this window, so IM is sized to cover it.

How does a CCP calculate initial margin?

Most use a VaR or expected shortfall model, often historical simulation, or a scenario grid, calibrated to a high confidence level and the MPOR. They then add buffers and charges such as concentration or liquidity add-ons.

Why is CCP margin procyclical?

Margin models use recent volatility, so IM rises when markets are stressed. This forces members to find more collateral at the worst time. Floors, buffers and stressed lookbacks reduce the effect.