How haio works
Methodology
haio turns recorded Singapore property transactions into practical research. This page explains our sources, how we compare homes, how we build estimates and market signals, and where the evidence stops.
Section 1
Data sources and coverage
We use official Singapore records wherever they are available. Source data may differ in publication timing, detail and historical depth, so every haio result depends on what its source records.
| Source | What we use it for | Access |
|---|---|---|
| URA | Private residential transactions, price indices and planning information. URA REALIS adds transaction detail that is not included in free public releases. | Public data and paid REALIS records |
| HDB and data.gov.sg | HDB resale transactions, property information and selected government datasets used in market research. | Public |
| SLA OneMap | Addresses, map coordinates and land-parcel context. | Public |
| SLA Cadastral Land Parcel | Land-lot boundaries for landed houses, used to draw a house’s own gate, frontage and lot walls on the 3D map. Accessed from data.gov.sg, made available under the Singapore Open Data Licence v1.0. | Public |
| MOE | Published Primary 1 vacancies and balloting outcomes. School distance is measured to the school boundary, following MOE distance-band rules. | Public |
| LTA DataMall and OpenStreetMap | Public transport and walking-network context for location tools. | Public, under their respective terms |
| MAS and IRAS | SORA reference rates, financing rules and property stamp-duty schedules used by our calculators. | Public |
What we cover
HDB, condominium, apartment, executive-condominium and private landed transactions, subject to each source’s published scope.
How often data changes
We refresh sources as new releases become available. A recent transaction can appear after its sale date because official records are published on their own schedules.
Section 2
Price estimates and comparables
A haio estimate starts with recorded sales of similar homes. It is an evidence-based market estimate, not a listing price, bank valuation or formal appraisal.
01
Find relevant sales
We keep property types and tenure groups separate, then favour sales that are nearby, recent and similar in size.
02
Put sales on a common basis
We compare price per square foot. For landed homes, the primary comparison is price per square foot of land.
03
Adjust meaningful differences
Where reliable data is available, we account for market timing, size, lease, floor, stack, property age and recorded rebuilds.
04
Estimate a value and range
Closer and more relevant sales carry more weight. We use a robust centre so one unusual sale cannot dominate the result, then show a range that reflects the available evidence.
Comparable sales shown on haio
Property pages show the recorded sales used as comparables so you can inspect them yourself. The table presents recorded prices and dates. The estimate can differ from a comparable’s headline price because adjustments are applied only when calculating the estimate.
Section 3
Confidence and limitations
Strong evidence produces a tighter range. Sparse or conflicting evidence produces a wider range, lower confidence or no estimate.
Thin markets
Rare property types and low-turnover enclaves may have few useful comparables. One sale is evidence, but it is not certainty.
Unrecorded differences
Renovation quality, views, defects, urgency and private deal terms may affect a price without appearing in transaction data.
New or unusual homes
A new launch, atypical plot or unusual unit may not have a true like-for-like resale comparison.
Missing transaction history
An address can exist in official mapping records without a sale in the available transaction record. In that case, the address is known but its market value is not.
haio is a research tool. It does not provide financial advice or a formal property valuation. For lending, legal proceedings or a binding sale decision, consult the appropriate licensed professional.
Section 4
Calculators
Lease decay
For leasehold homes with a known lease start, haio illustrates how remaining tenure can affect value using Bala’s Table. It is a standard leasehold-value curve, not a forecast of the home’s future sale price. Freehold homes and homes with insufficient lease information receive no lease-decay estimate.
Affordability
The affordability calculator applies published MAS financing rules to the income, debt, loan and property details you enter. It considers applicable loan-to-value, TDSR and MSR constraints. Banks may apply additional checks, so the result is an estimate, not a credit decision.
Mortgage payments
Payment estimates use a published SORA reference plus an adjustable bank spread. Affordability checks may use a different regulatory stress rate. Actual packages, fees and approval terms vary by lender.
Stamp duty
Buyer’s Stamp Duty, Additional Buyer’s Stamp Duty and Seller’s Stamp Duty estimates follow published IRAS schedules and the details you provide. Remissions, refunds, transitional rules and unusual ownership structures may require separate review. Confirm the final amount with IRAS or a qualified adviser.
Section 5
Market signals
En-bloc likelihood
This is a relative tier, not a probability. It compares eligible private developments using factors such as age, remaining lease, planning headroom, project size and relevant collective-sale history. Owner consent, reserve price and buyer demand are not observable in advance, so the tier is a research prompt rather than a forecast.
Selling pressure
Selling pressure is a relative rank built from aggregate market signals. For private projects, these can include holding periods, seller-stamp-duty eligibility and recorded resale outcomes (the share of resales sold above the same unit’s previous sale price; a resale with no previous sale of that exact unit on record is not counted, and nothing is estimated). For HDB blocks, the signal centres on estimated Minimum Occupation Period timing. It does not predict whether a particular owner will sell.
Exit risk
Exit risk compares a recent project-level resale benchmark with the recorded entry prices of traced current owners. It describes how much lower-priced supply may exist within a project. A high share can be normal in a project that has appreciated over time, so it should be read with the sample size, holding periods and transaction history.
Section 6
Privacy and responsible use
Market signals are presented at property, project or block level. We do not publish owner names or identify a person behind a transaction. Small or unreliable samples may be suppressed, and signals are withheld when the available evidence does not support a responsible result.
Section 7
How to cite haio
Cite the original agency for a fact reproduced directly from public records. Cite haio for a haio estimate, ranking, comparison or other derived result. Link to the relevant property page so readers can see the context and available evidence.
Suggested format
Source: haio, based on Singapore government property records. Retrieved [date] from [property page URL].