A rental property cash-flow projection maps every dollar in against every dollar out each month. This guide walks through gross rent, vacancy allowance, mortgage interest, property tax, maintenance fees, and insurance — then shows a worked Singapore example (as of 2026-06) that reveals whether your investment puts cash in your pocket or requires a monthly top-up.
You have signed the tenancy agreement, handed over the keys, and the first month's rent hits your account. But after the mortgage instalment clears, the property-tax GIRO deducts, and the MCST levy arrives, how much is actually left? For many Singapore landlords — especially those holding prime-district condos purchased at compressed yields — the honest answer is: less than expected, sometimes negative. Building a cash-flow projection before you buy, and updating it every year of ownership, is the single most grounding exercise an investment-property owner can do. It converts vague optimism about "rental income" into a line-by-line monthly scorecard you can act on.
Why cash flow is not the same as yield or total return
Gross rental yield tells you rent as a percentage of purchase price. Net yield adjusts for costs. Neither figure tells you whether you need to write a cheque each month. Cash flow is the only metric that answers the question: "After every outgoing is paid, how much cash lands in my bank account?" (as of 2026-06)
Total return adds capital appreciation and principal pay-down (equity build) on top of cash flow. A property can deliver strong total return over ten years while generating mildly negative monthly cash flow the entire time — as has been the case for many CCR (Core Central Region) condos in Singapore. Separating these three concepts prevents the common mistake of conflating "my property went up in value" with "my property generates income."
The inputs you need before you start
Gather these figures before building your projection:
- Gross monthly rent — current market rent for comparable units. Check URA rental data or our rental yield map for district benchmarks (as of 2026-06).
- Outstanding loan balance and loan terms — fixed or floating rate, remaining tenure, monthly instalment.
- Annual value (AV) of the property — set by IRAS, used to compute property tax. Retrieve yours at the IRAS property tax portal.
- MCST monthly levy — from your management corporation statement.
- Home insurance premium — divide annual premium by 12.
- Historic repairs — estimate from past bills or use a rule of thumb of 0.5–1% of property value annually.
- Agent leasing commission — typically one month's rent for a 2-year tenancy; divide by 24 to amortise monthly.
Your agent says the rental yield is 3.5%. But after mortgage payments, MCST, property tax, insurance, agent fees, vacancy, and income tax, what is your actual monthly cash flow? Is it positive or negative? And how many years until your cumulative cash flow turns positive?
The Cash Flow Projection Tool answers these questions year by year across three scenarios — optimistic, base, and pessimistic — so you know the best and worst cases before you commit.
What This Calculator Does
Project year-by-year rental cash flow across three scenarios — optimistic, base, and pessimistic. See when your cumulative cash flow turns positive, compare ROI at years 5 and 10, and stress-test your investment thesis with different rent, appreciation, and vacancy assumptions.
You can find this calculator in the Calculators tab on ShiokNest. It updates results instantly as you adjust inputs — no waiting, no page reloads.
Why This Matters
Gross rental yield does not equal cash flow. Many properties with attractive headline yields of 3-4% are actually cash-flow negative month after month once you factor in mortgage payments, IRAS property taxproperty tax, maintenance, and vacancy. This calculator matters because:
- It separates yield (paper return) from cash flow (money in your bank account)
- Three scenarios (optimistic, base, pessimistic) show the range of possible outcomes
- Year-by-year projections reveal when cumulative cash flow turns positive
What You Will Discover
After running this calculator with your personal numbers, you will know:
- Year-by-year cash flow across three scenarios (optimistic, base, pessimistic)
- The break-even year when cumulative cash flow turns positive
- ROI at years 5 and 10 under each scenario
- Monthly carrying costs including mortgage, tax, and maintenance
- Whether your investment survives the pessimistic scenario without external top-ups
Key Inputs Explained
Here are the inputs you will configure, along with their default values. Each default is calibrated to a realistic Singapore condo scenario so you can explore results immediately.
| Field | Description | Default Value |
|---|---|---|
| Purchase Price | The total property price before additional costs. | $1,500,000 |
| Down Payment (%) | Your cash/CPF contribution as % of price. | 25.0% |
| Interest Rate (%) | Annual loan interest rate. | 3.5% |
| Loan Tenure (Years) | Duration of the mortgage loan. | 25 years |
| Monthly Rent | Expected monthly rental income or rent you would pay. | $4,500 |
Step-by-Step Guide
- 🏠 Navigate to Calculators — Click the "Calculators" tab in the ShiokNest navigation bar. All 26 calculators are grouped by purpose for easy access.
- 🔍 Select the calculator — Choose "How to Project Rental Property Cash Flow" from the calculator list. You will see default values already loaded so you can explore immediately.
- ✏️ Enter your values — Replace the defaults with your own numbers. The key fields are:
- Purchase Price — The total property price before additional costs.
- Down Payment (%) — Your cash/CPF contribution as % of price.
- Interest Rate (%) — Annual loan interest rate.
- Loan Tenure (Years) — Duration of the mortgage loan.
- Monthly Rent — Expected monthly rental income or rent you would pay.
- 📊 Review the results — The calculator updates instantly as you change any input. Year-by-year cash flow across 3 scenarios, break-even year, and ROI at years 5 and 10.
- 🔄 Run what-if scenarios — This is where the real power lies. Change one variable at a time to see its impact. For example, try increasing the interest rate by 1% or extending your holding period by 5 years. Note how the results shift.
- 💾 Compare and decide — Run 2-3 different scenarios and note the results. This gives you a range of outcomes to base your decision on, rather than relying on a single projection.
Worked Example
Meet Marcus, buying a $1,500,000 condo for rental investment at $4,500/month. He puts 25% down and takes a 25-year loan at 3.5%. Is this property cash-flow positive?
| Scenario | Rent | Vacancy | Monthly Cash Flow |
|---|---|---|---|
| Optimistic | $4,950 | 2% | +$-1,531 |
| Base | $4,500 | 5% | -$2,107 |
| Pessimistic | $4,050 | 10% | -$2,737 |
The three-scenario reality: Marcus's investment looks viable in the optimistic scenario, but the pessimistic scenario (lower rent, higher vacancy) turns cash-flow negative. The calculator projects these year by year, showing when cumulative cash flow turns positive and what ROI looks like at years 5 and 10.
Real-World Scenarios to Try
Here are some realistic scenarios you can plug into the calculator right now. Each one reflects a common situation Singapore property buyers face.
| Scenario | Settings to Try | What You Will Learn |
|---|---|---|
| Conservative investor | $1.5M, 75% LTV, $4,500 rent, 8% vacancy | Year-by-year cash flow across 3 scenarios — when you turn cash-positive |
| High-leverage play | $2.0M, 75% LTV, $5,500 rent, 3% apprec. | How leverage amplifies both returns and risk over a 25-year horizon |
| Stress test | $1.8M, $4,000 rent, 15% vacancy, 1% apprec. | Whether your investment survives a prolonged downturn (pessimistic scenario) |
Expert Tips and Common Pitfalls
💡 Pro Tips
- Use realistic assumptions — Singapore condo appreciation has historically averaged 2-4% per year. Avoid overly optimistic projections. When in doubt, use 3% as a baseline.
- Be conservative with vacancy — Even in a hot rental market, budget for 1-2 months vacancy between tenants. A 5% vacancy assumption is the minimum.
- Factor in MCST increases — Condo maintenance fees rise 3-5% per year on average. The pessimistic scenario should reflect this reality.
- Do not rely on the optimistic scenario — The base and pessimistic scenarios are where your investment thesis needs to survive. If it only works in the best case, it is too risky.
⚠️ Common Pitfalls
- Using gross yield as a proxy for cash flow — A 3% gross yield property can still be deeply cash-flow negative after mortgage, tax, and maintenance.
- Ignoring capital expenditure — Major repairs (aircon replacement, waterproofing) happen every 5-7 years and are not covered by MCST fees.
🤔 What-If Scenarios to Explore
Get the most value from this calculator by testing these scenarios:
- Compare a high-rent OCR condo ($3K/month) vs a premium CCR unit ($6K/month) — which has better cash flow?
- What if vacancy rises to 15% due to oversupply? Does your investment survive the pessimistic scenario?
- What if interest rates jump to 5%? How many years until break-even?
- Run at least 3 scenarios — best case, base case, and worst case — to understand the full range of outcomes.
Related Calculators
Your property journey involves many interconnected decisions. These calculators work hand-in-hand with this one:
- How to Calculate Buy-to-Rent ROI
- How to Use the End-to-End Investment Calculator
- How to Optimize Your Holding Period
Ready to Crunch Your Numbers?
Enter your property details and rental expectations. See year-by-year cash flow across three scenarios. Know exactly when your investment starts generating positive returns.
Official Sources
This how-to guide is auto-generated using ShiokNest's calculator defaults. All worked examples use default values — adjust inputs to match your personal scenario for accurate results.
The inflow side: accounting for vacancies
Gross rent is not the same as collected rent. Even a well-located property sits vacant between tenancies — during the search period, minor refurbishment, or when a tenant gives short notice. A conservative projection assumes one void month per year, which reduces effective annual rent by approximately 8.3%. On a $3,500/month unit, that is a $291/month reduction on an annualised basis ($3,500 × 11 ÷ 12 = $3,208 effective monthly inflow).
Some landlords buffer further by assuming a slight rent reduction on renewal — if you plan to retain a good tenant at a 5% discount rather than risk a vacancy, model that downside case too. Use our cash-flow calculator to stress-test different vacancy and rent assumptions side by side.
The outflow side: separating true costs from equity build
The mortgage instalment has two components. The interest portion is a true cost — money paid to the bank that does not return to you. The principal portion reduces your loan balance and builds equity; it is not a cash cost in the accounting sense, but it absolutely requires a cash outflow each month. For cash-flow purposes, include the full instalment as an outgoing. For yield and total-return analysis, you may wish to strip out principal — but never omit it from cash-flow projections, because that cash leaves your account regardless.
As of 2026-06, the Singapore Overnight Rate Average (SORA) 3-month compounded rate sits in the 3%–3.5% range, and most floating-rate mortgages are priced at SORA plus a bank spread of around 0.7%–1.0%. Fixed-rate packages for new loans are broadly in the 2.8%–3.3% range. Check the MAS interest rate statistics for the latest benchmarks before modelling your projection.
Property tax for non-owner-occupiers applies at a higher progressive rate than the owner-occupier schedule. For the 2026 assessment year, IRAS non-owner-occupier rates start at 12% on the first $30,000 of AV and step up from there. For a typical mass-market condo with an AV of $36,000, annual property tax is approximately $4,320, or $360 per month. For a CCR unit with an AV of $60,000, the annual bill climbs to around $8,400 (approximately $700/month).
Worked example: a $1.6 million OCR two-bedder (as of 2026-06)
Assumptions: purchase price $1.6 million, 25% down payment ($400,000), loan $1.2 million over 25 years at 3.2% fixed. Gross rent $3,800/month. AV $36,000. MCST levy $250/month. Home insurance $55/month. Amortised leasing commission $146/month (1 month rent ÷ 24). Repair reserve $80/month.
| Line item | Monthly ($) |
|---|---|
| Gross rent | +3,800 |
| Vacancy allowance (1 month/year) | −317 |
| Effective inflow | +3,483 |
| Mortgage instalment (P+I) | −5,836 |
| Property tax (non-OO, AV $36k) | −360 |
| MCST levy | −250 |
| Home insurance | −55 |
| Repairs reserve | −80 |
| Leasing commission (amortised) | −146 |
| Total outflow | −6,727 |
| Net monthly cash flow | −3,244 |
The landlord tops up $3,244 each month. This is not unusual in Singapore at current rates. Of the $5,836 instalment, roughly $3,200 is interest (cash cost) and $2,636 is principal (equity build). Adjust the mortgage calculator to see how a rate increase from 3.2% to 4.0% would push the instalment to approximately $6,310, widening the monthly shortfall by a further $474. For district-level rental benchmarks that help you sense-check your gross rent assumption, explore the rental yield map.
Step-by-step: build your projection in six steps
- Establish your gross monthly rent. Use the last 3–6 months of URA rental transactions for your street and unit size as the benchmark. Be conservative — model the midpoint, not the top-of-range transaction. Apply a vacancy factor of one month per year by multiplying gross rent by 11/12.
- Calculate your full mortgage instalment. Use our cash-flow calculator or a standard amortisation formula. Record the full instalment (principal + interest) as an outflow. For sensitivity analysis, also compute the instalment at a rate 0.5% and 1.0% higher than your current rate to understand your downside exposure.
- Compute your property tax. Retrieve your property's annual value from the IRAS portal. Apply the non-owner-occupier rate schedule (as of 2026-06): 12% on first $30,000 AV, 20% on next $15,000, then 28% above. Divide the annual bill by 12 for your monthly figure.
- List all recurring costs. Pull three months of bank statements and identify every recurring property-related debit: MCST, insurance, any concierge or facility-access fees. Add a repair reserve — a commonly used rule of thumb is $50–$100/month for a condo unit under 15 years old, rising to $100–$200/month for older stock where plumbing and aircon replacements become more likely.
- Amortise one-off costs. Leasing agent commission (typically one month's rent for a 2-year lease) should be divided by 24 and treated as a monthly cost. Renovation for a new tenancy can be treated similarly — divide the total spend by the expected lease length in months.
- Calculate net cash flow and run scenarios. Subtract total outflow from effective inflow. Then run three scenarios: (a) base case — current rent, current rate, one void month per year; (b) downside — rent 10% lower, rate 0.75% higher, two void months; (c) upside — rent 5% higher, rate flat, no void. If the downside scenario produces a monthly shortfall you cannot comfortably absorb from other income, that is a risk to address before or at the time of purchase.
Frequently asked questions
Is negative cash flow always a bad sign for a Singapore rental property?
Not necessarily. Negative cash flow means you are topping up each month, but if capital appreciation and equity build (principal pay-down) together exceed that shortfall over your holding period, total return can still be positive. Many CCR landlords in Singapore have run modest negative carry for years while their units appreciated significantly. The key question is whether the negative cash flow is sustainable within your income and whether your total-return thesis — including realistic capital growth assumptions — is sound. Negative carry is a risk, not an automatic disqualifier (as of 2026-06).
How does the non-owner-occupier property tax rate compare to the owner-occupier rate?
The gap is significant. For the 2026 assessment year, owner-occupiers pay 0% on the first $8,000 of annual value, then 4%–16% on higher bands. Non-owner-occupiers — which includes all landlords renting out their property — pay 12% on the first $30,000 of AV, stepping up to 20% and 28% on higher bands. On a property with AV of $36,000, an owner-occupier pays roughly $480/year while a landlord pays approximately $4,320/year. This difference alone can represent $320/month in additional outflow compared with an owner-occupied scenario. Always retrieve your actual AV from the IRAS portal before finalising projections.
Should I include the principal repayment portion of my mortgage in the cash-flow projection?
Yes, for cash-flow purposes. Your bank account does not distinguish between interest and principal — both portions leave your account with each instalment. Cash-flow projections measure liquidity: can the rent cover your monthly obligations without requiring you to inject personal funds? Principal repayment must be included to answer that question honestly. You may separately note the principal component as equity build when assessing total return, but omitting it from the cash-flow line distorts the picture and leads landlords to overestimate how much the property "pays for itself."
How should I handle the agent leasing commission in my projection?
Amortise it over the lease term. A 2-year tenancy with one month's rent commission at $3,800 means $3,800 spread over 24 months — approximately $158/month. This approach smooths the irregular timing of commission payments and gives you a cleaner monthly cost picture. If you plan to use an agent for every renewal, build this as a permanent line item. Some landlords manage renewals directly to save the fee, but even then, budget for occasional advertising costs and vacancy days during the search period.
What is a realistic repair and maintenance reserve for a Singapore condo?
A commonly cited rule of thumb is 0.5%–1% of property value per year for all maintenance and repair costs, excluding the MCST levy (which covers common-area upkeep separately). On a $1.2 million unit, that is $6,000–$12,000 annually, or $500–$1,000/month. In practice, a condo under 10 years old with no major appliance cycles due may run at the lower end; a 15-to-20-year-old unit approaching an aircon overhaul or bathroom refurbishment cycle should be budgeted at the higher end. Always check the MCST sinking fund status — a depleted sinking fund signals upcoming special levies that are not captured in the monthly fee.