BCIS alternatives: free UK construction cost data for small practices
What the free sources cover, where they fall short, and how to stitch them together.
All four figures pulled live from ONS and MHCLG sources. They're the same numbers BCIS reports, just reached by a different (free) path.
BCIS is the UK's standard construction cost data service and it's excellent, but at roughly £600 to £2,000 a year, it's priced for larger practices and public-sector QSs. For a small design-build firm with one QS and budget scrutiny, the subscription often doesn't make the cut.
The good news: between ONS, MHCLG, Costmodelling and the free market reports from the major consultancies, you can cover most of what a small-practice QS actually needs for free. This page compares the options, flags where each falls short, and explains how to stitch them together.
The free sources compared
| Source | What it covers | Update | Regional | Free? |
|---|---|---|---|---|
| BCIS (RICS) | Tender price index, elemental cost plans, building costs by type | Quarterly, live online | ✓ | Paid |
| ONS Construction Output Price Indices | Blended output prices (new work + R&M), UK aggregate | Quarterly (~6 weeks lag) | No | ✓ |
| MHCLG Monthly Building Materials | ~15 individual material indices (bricks, timber, steel, etc.) | Monthly | No | ✓ |
| Costmodelling.com | Indicative tender / building cost indices, regional factors | Periodic, not live | ✓ | ✓ |
| Turner & Townsend / Gleeds market reports | Narrative commentary, forecast direction, anecdotal benchmarks | Quarterly or annual PDFs | ✓ | ✓ |
| Trails Cost Tracker | ONS + MHCLG aggregated; regional factors; interactive adjustment | Live; refreshed each quarter | ✓ | ✓ |
What each source does well (and doesn't)
BCIS (RICS)
Strength: Gold standard; elemental breakdowns unmatched elsewhere
Weakness: Subscription; out of reach for small practices
ONS Construction Output Price Indices
Strength: Authoritative, openly licensed, used in public contracts
Weakness: Blended only; no regional split; no elemental breakdown
MHCLG Monthly Building Materials
Strength: Granular material-specific signal; earliest indicator of input shocks
Weakness: Materials only; no labour; flat CSVs that need parsing
Costmodelling.com
Strength: Free regional factors in a usable form
Weakness: Static HTML; no interactive tools; irregular updates
Turner & Townsend / Gleeds market reports
Strength: Good for narrative context and forecasts
Weakness: Not a dataset; hard to use programmatically
Trails Cost Tracker
Strength: Combines free sources with an interactive tool + inflation adjustment
Weakness: Not elemental (yet); blended where ONS is blended
How to stitch them together
For most small-practice use cases, this combination gets you roughly 90% of what BCIS would:
- Inflation adjustment on historical quotes: Use the ONS Construction Output Price Index via the Trails Cost Tracker. It applies the multiplier for you, including quarter-to-quarter precision.
- Per-m² benchmarks by project type: Turner & Townsend and Gleeds publish indicative ranges in their free annual reports. Trails publishes a live-adjusted benchmark table that combines these with current ONS adjustment.
- Material price signals: MHCLG's monthly building materials dataset is granular and free. The Cost Tracker surfaces the most-watched 10 to 15 commodities as a live grid.
- Regional factors: Costmodelling publishes a usable table, and the same factors are applied automatically in the Cost Tracker when you select a region.
- Market narrative / forecasts: Turner & Townsend's quarterly market intelligence and Gleeds' annual construction review are both free PDFs and good for the "where are costs going?" conversation with clients.
Where BCIS is still worth it
Three cases where the BCIS subscription earns its keep:
- Elemental cost plans at NRM2 level of detail. BCIS's element-by-element breakdowns by building type aren't matched in any free source. If you're doing cost-plan work regularly from scratch, the saved hours justify the cost.
- Non-residential tendering. Free sources are heavily residential-biased. For commercial, healthcare, education or industrial work, BCIS is still the shortest path to defensible numbers.
- Large-project dispute support. BCIS data has a court-tested provenance that free sources don't yet have. For PI or adjudication contexts, the pedigree matters.
For residential extensions, refurbishments, and small new-build work (the typical small design-build portfolio), the free stack is usually enough.
A quick rule of thumb
If your firm bills under ~£1m/year and your QS is a generalist who spends less than 20% of their time on cost planning from scratch, the free stack covers you. Above that, or if you're pricing commercial work, BCIS pays back.
Either way: the data above is always live on the Trails Cost Tracker and free to use.