How to Calculate a Systematic Transfer Plan

Follow both sides of the transfer

An STP projection tracks the invested balance that supplies each transfer and the separate balance that receives it. A transfer changes the allocation immediately. Combined value changes as the balances earn their respective modeled returns.

What an STP projection measures

A systematic transfer plan (STP) moves amounts from a source investment to a destination investment. This model starts with one source balance and an empty destination.

The model keeps the transfer inside the combined portfolio. Actual switching can involve redemptions and subscriptions and may follow separate product rules.

Compare transfer schedules

Run the same opening amount and rates at different monthly requests to see how quickly funds move and whether the source can fund the whole schedule. Try equal rates to isolate the allocation effect.

STP formula and order

Convert each effective annual decimal rate A to its monthly factor (1 + A)^(1/12). Beginning timing moves the funded amount before both balances grow. End timing grows both balances first. Each funded amount is the lesser of the request and available source.

Funded transfer = min(monthly request, available source)

Reconcile a partial transfer

With a source balance of 1,000, a monthly request of 400, zero returns and three months, transfers are 400, 400 and 200. The source ends at zero, the destination at 1,000 and the combined value at 1,000. Unmet requests total 200 and signed growth is zero.

If the request is 500 instead, month 2 moves the final 500 in full. In a three-month horizon, the first shortfall then occurs in month 3 and funds zero.

1. Enter 1000 as opening source and 400 as monthly transfer.
2. Enter zero for both annual rates and three months.
3. Check the combined value, funded total and the 200 transferred at the first shortfall.

Separate allocation from growth

The combined ending value equals opening source plus signed modeled growth. Requested less funded equals unmet. A full transfer can deplete the source before any request goes unfunded.

At equal rates each unit of capital experiences the same growth factor wherever it is held. With unequal rates, the timing changes how long transferred amounts experience each rate.

Enter two rates and choose timing

Enter the opening source, fixed monthly request, both effective annual percentages and complete months. Choose beginning or end timing. Read the balances, monthly rates and transfer outcomes together.

Enter both rates explicitly, using zero for a flat assumption. Use the same currency for the opening amount and requests.

Choose between STP, SIP and SWP

Use STP for two connected investment balances. Use the SIP calculator for fixed contributions from outside the portfolio and the SWP calculator for withdrawals that leave the portfolio.

Understand the checkpoint convention

Both balances use equal model months and the destination starts at zero. The same funded amount leaves the source and enters the destination immediately. The first request is labeled month 1 for either timing.

A beginning transfer first affects growth in that month. An end transfer first affects growth in the following month.

Respect the projection limits

Opening amount and monthly request range from 0 to 10^12, horizon from 0 to 1,200 months and each annual percentage from above −100% to 100%. Decimals allow 12 fractional places. Arithmetic uses at least 100 significant digits, flags unresolved funding thresholds and rejects combined ending values above 10^30.

The source can fund a partial amount. Actual provider minimums and instructions may handle insufficient balances differently.

Avoid counting the transfer twice

Do not add funded transfers to the combined value again. Check whether another calculator applies returns before or after the switch, and whether the annual rates use the same basis.

Use effective annual rates. For example, 12% effective annual growth implies about 0.948879% monthly.

Use one currency across both investments

In India, STP and scheme switching are common terms. In the USA, UK, Canada and Australia, phased transfers between investments describe this modeled scenario. Choose USD, GBP, CAD, AUD or INR for display. Local account rules and product eligibility are outside the model.

Educational scope

Educational constant-return projection in one currency. It excludes dates, eligibility, settlement, NAV, taxes, fees, inflation, FX and changing market returns. It does not provide personalized investment advice.

Frequently asked questions

Sources and review

Sources reviewed Nov 10, 2026. Consult current local rules before relying on time-sensitive information.

• HDFC Mutual Fund STP calculator
• AMFI-hosted scheme disclosure
• Investor.gov rebalancing guide
• MoneyHelper investing overview
• OSC investor education
• ASIC Moneysmart calculator