Copying trades between cent and standard accounts: how lot sizes work

What a cent account is

A cent account keeps its balance in cents of a currency. The currency is shown as USC (US cents) or EUC (euro cents). A balance of 200,000 USC is 2,000 USD. Brokers offer them so that traders can start with very small amounts.

SnapCopier treats an account as a cent account when its currency is USC or EUC. There is nothing to switch on.

Why lot sizes differ

Brokers build cent accounts in one of two ways, and in both the result is the same: one lot on a cent account is worth about a hundredth of a lot on a standard account.

• A smaller contract. For example, EURUSD.c has a contract size of 1,000 instead of 100,000.
• A standard contract with profit counted in cents. The lot is the usual size, but the profit and loss are booked in cents, so it is worth a hundredth.

A copier has to know which one the broker uses, otherwise it converts twice or not at all. It works this out for each account, so you do not have to.

What is converted automatically

When exactly one of the two accounts is a cent account, the lots are scaled by 100 in the right direction, and the balance of the cent account is converted too (USC to USD is the amount times 0.01). With the lot sizing set to proportional, the same share of the balance is traded on both sides:

Both are the same real size: 2,000 USD of equity and a trade of one hundredth of a standard lot.

A worked example with different balances

The master is a cent account with 3,000 USC, which is 30 USD, and opens 0.10 lot. The follower is a standard account with 5,000 USD. The follower is about 167 times bigger.

Proportional to balance is the one that keeps the follower’s risk in line with the master’s: the same share of its balance on every trade.

Why a multiplier of 100 is not the fix

It is tempting to set “Master lot × N” to 100, because the lots look too small. But the cent conversion is already applied, so multiplying by 100 cancels it: the follower opens the same number of lots as the master, which is a different amount of risk for each pair of balances.

In the example, the follower with a multiplier of 100 opens 0.10 lot, and takes 0.6 times the master’s share of its balance. With a follower of 500 USD it would be 6 times, and with 50 USD 60 times. A multiplier ignores the balances, so it can only be right for one pair of accounts.

Small trades and the minimum lot

From a cent master to a smaller standard follower the proportional lot can fall below the broker’s minimum, usually 0.01. For example, a master with 200,000 USC opening 1.00 lot and a follower with 500 USD: the proportional lot is 0.0025.

Below minimum lot decides what happens: the trade is skipped, or the minimum lot is opened. Opening the minimum is a larger share of a small balance than the master’s trade was, up to many times larger, so choose it knowingly. The sample calculation in the copy settings warns when the minimum is at least twice the proportional size.

A cent account that is labelled USD

Some brokers label a cent account as plain USD: a balance of 200,000 “USD” that is really 2,000 USD. To a copier it looks like an ordinary account, with every number a hundred times bigger. With the lot sizing set to proportional, the factor of 100 cancels out and the copies are sized correctly. With a multiplier, the lot count is copied, not the value, so the real size differs by 100: set the multiplier yourself, or use proportional sizing.

Before you go live

1. 1Look at the currency of both accounts in the account list: USC or EUC marks a cent account.
2. 2Use Proportional to balance, and keep the risk factor at 1 until you have seen a few copies.
3. 3Check the sample calculation and the “Slave risk vs master” line in the copy settings.
4. 4Decide what Below minimum lot should do.
5. 5Try it on demo accounts first. How lot sizes are calculated covers the other modes.

Questions