ETF Portfolio Growth Calculator — Compound Interest

Final Portfolio Value

—

Total Growth

—

Return

Monthly Income (4%)

—

Safe Withdrawal

Coast Growth

—

Passive Accretion

// Portfolio Inputs

Starting Sum ()

Monthly Contribution: —

Annual Return: 7.0%

// Investment Horizon

Years Contributing: 10

Years Coasting After: 10

The Coasting Rule

At year 10, your contributions stop. Your portfolio continues to compound on its own for the remaining 20 years.

// Accumulation Curve

// Year-by-Year Breakdown

Year	Contribution	Growth	End Balance	Phase

How the ETF Growth Model Works

This tool projects the long-run growth of a regular ETF investment programme. Enter a lump-sum starting balance, a fixed monthly contribution, an assumed annual return, and a time horizon. The model uses a mid-year contribution approximation — your monthly contributions are treated as arriving evenly throughout the year — which produces a more realistic outcome than assuming all contributions land on 1 January.

The output breaks your final balance into three components: the original lump sum compounded forward, the total contributions you made, and the investment return earned on top of both. This decomposition helps you see how much of your outcome is within your direct control (contributions) versus dependent on markets (returns).

Frequently Asked Questions

What ETF return should I assume?

▼

Broad global equity index funds (e.g. MSCI World trackers) have returned roughly 8–10% per annum in nominal USD terms over the past 30 years. After inflation and fees, a real return of 5–7% is a common planning assumption. We recommend stress-testing your plan at 5%, 7%, and 9% to understand the range of outcomes.

Which ETF platforms are available to Gulf expats?

▼

As a non-UK resident, your options differ from onshore investors. Interactive Brokers is available to UAE residents and offers low-cost access to UCITS ETFs listed on European exchanges. Saxo Bank and Swissquote are also commonly used. Avoid the offshore savings plans aggressively marketed to expats — these typically lock in high fees for 25 years.

Should I invest in USD, GBP, or AED-denominated ETFs?

▼

UCITS ETFs listed on the London Stock Exchange (LSE) trade in USD and GBP variants of the same underlying fund. The currency of the share class does not change your underlying currency exposure — a global equity ETF is mostly USD-exposed regardless of the share class denomination. Choose GBP if you plan to retire in the UK; USD if your retirement spending will be dollar-linked.

How does dollar-cost averaging affect the projection?

▼

The model assumes a fixed monthly contribution — this is effectively dollar-cost averaging. You buy more units when prices are low and fewer when high, smoothing your average entry price over time. This is the primary advantage of regular investing over trying to time the market with lump sums.