Savings Goal Calculator — How Long Will It Take to Save? (2026)

A clear savings goal needs three numbers: how much you want, how much you can put in each month, and how long that takes. This calculator computes the third when you have the first two — useful for setting realistic timelines on house deposits, car purchases, holidays, business investment, or emergency funds.

How the maths works

Future value of regular savings = (monthly contribution × (((1 + r)^n − 1) / r)) + (starting balance × (1 + r)^n)

where r is the monthly interest rate (annual ÷ 12) and n is the number of months. The calculator solves for n when given a target future value. The non-linear shape of the equation means small changes in interest rate or contribution amount have outsized impact on time-to-goal at long horizons.

Worked example

Goal: $80,000 house deposit. Starting: $5,000. Contribution: $1,000/month. Rate: 5%.

• Months to goal: ~67 (5.6 years)
• Total contributions: $67,000
• Interest earned along the way: $8,000

If you bumped contribution to $1,500/month:

• Months: ~46 (3.8 years)
• Total contributions: $69,000
• Interest: $6,000

The 50% increase in contribution buys you 21 months back — substantial.

Choosing the right interest rate

The rate matters enormously and depends on the asset:

• Online savings account (4-5%) — appropriate for short-term goals (<3 years), highly liquid
• Term deposit (5-5.5%) — appropriate when you can lock funds for the term
• Balanced ETF (~5-7% expected long-run) — appropriate for 5-10 year goals
• Equity-heavy portfolio (~7-9% expected long-run) — appropriate for 10+ year goals

Use conservative rates for short-term goals (volatility risk), and confident long-run rates for very long horizons (volatility averages out).

Boosting the savings rate

For most savers, the highest-leverage levers (in order of impact):

1. Increase contribution amount — direct linear impact. Even +$200/month makes large differences.
2. Auto-debit on payday — removes the willpower cost. The contribution happens before discretionary spending.
3. Direct windfalls — tax refund, bonus, gift money — straight into the goal account before they're absorbed into general spending.
4. Increase rate — move money from a 0.5% transaction account to a 4-5% high-interest savings or 5%+ TD. Same money, more growth.
5. Reduce discretionary expenses — every $50/month redirected to savings adds up over years.

When to take more risk for faster timeline

Two-edged sword. Switching from a 5% high-interest savings to an 8%-expected ETF cuts the timeline meaningfully but introduces volatility — you might hit your goal earlier OR later, depending on when in the cycle you sell.

For goals < 3 years: don't take equity risk. The volatility is asymmetric — a 30% drawdown 6 months before settlement derails the entire plan.

For goals 3-7 years: a balanced portfolio (50/50 or 60/40 equities/defensive) typically wins on average but with real downside risk.

For goals 7+ years: equities historically outperform, and you have time to ride out drawdowns.

When the timeline doesn't work

If the calculator shows your goal is 15+ years away and that doesn't feel acceptable, three options:

1. Reduce the goal — smaller deposit, smaller car, shorter holiday. Realism over aspiration.
2. Extend the timeline — accept the longer wait if the goal is genuinely worth waiting for.
3. Increase contribution — find more in the budget, work toward higher income, or both.

The savings calculator is honest about what's mathematically possible. If the answer is unsatisfactory, the levers are real things — not optimism.