Asking-rent index (portal listings, ONS-validated)
asking_rent_index_seriesHedonic ASKING-RENT index for one postcode district, local authority or Great Britain, from portal lettings, 2022M01 = 100, with bands and SEs. This is the residential rent index; commercial_rent_index_series is the VOA one for commercial property.
Same call over REST
Market rent index/v1/market/rent-indexNot connected yet? Connect your assistant. Sign in with your MarketCode account; no API key needed.
Reference
What asking_rent_index_series answers
It is validated every build against the ONS Price Index of Private Rents by local authority and NOT published in a month where the two disagree by more than a few points a year — so a missing recent month is a refusal, not an outage; say so. Asking rents, not achieved; value is an index level, never a rent. For rent LEVELS and yields use listing_market_series.
Same area and frequency rules as asking_price_index_series.
Inputs
Before you call it
- area_code
- The area code is a postcode district ("W14") with
area_typeset to district, or a local authority name ("Camden", not a GSS code) witharea_typeset to lad. No lookup is needed. An unknown area returns an error naming the nearest matches; read them back rather than guessing.
Example
An example call to asking_rent_index_series
Use the MarketCode tool asking_rent_index_series with {"area_code":"Lewisham","area_type":"lad","limit":6} and show me the result.{
"country": "UK",
"query": {
"area_code": "Lewisham",
"area_type": "lad",
"frequency": "monthly",
"method": "hedonic_smoothed",
"limit": 6
},
"data": {
"area": {
"scope": "lad",
"area_key": "c0694b59-04d1-48ab-9a4c-c4f9d7b74f60",
"area_code": "Lewisham",
"area_name": "Lewisham"
},
"frequency": "monthly",
"basis": "Hedonic (mix-adjusted) index of ASKING rents from portal listings, 2022M01 = 100, smoothed toward the parent geography with posterior standard errors. Validate…",
"series": [
{
"period": "2026M03",
"period_start": "2026-03-01",
"value": 110.37210808439843,
"lo": 109.16951798868122,
"hi": 111.58794567781428,
"se_pp": 0.8548678811047612,
"inc_se_pp": 1.0646344730950843,
"yoy_pct": 0.9445566632207524,
"n_obs": 897,
"is_provisional": false
},
{
"period": "2026M04",
"period_start": "2026-04-01",
"value": 113.90924450636952,
"lo": 112.63086068539413,
"hi": 115.20213825103538,
"se_pp": 0.8806730125610661,
"inc_se_pp": 1.0667307051832329,
"yoy_pct": 3.953846881750178,
"n_obs": 897,
"is_provisional": false
},
{
"period": "2026M05",
"period_start": "2026-05-01",
"value": 105.42554586082936,
"lo": 103.07052363030782,
"hi": 107.83437716799968,
"se_pp": 1.7628262936279937,
"inc_se_pp": 1.6907054539964568,
"yoy_pct": -6.0246877053665155,
"n_obs": 68,
"is_provisional": true
},
"… 3 more"
],
"provenance": {
"source_table": "marts_facts.listing_index",
"basis": "asking_rent",
"method": "hedonic_smoothed",
"pub_freq": "quarterly",
"parent_key": "NATIONAL",
"base_period": "2023 mean",
"n_obs_total": 41207,
"n_periods": 6,
"first_period": "2026M03",
"last_period": "2026M08",
"built_at": "2026-09-05T11:16:13.107592+00:00",
"validation": "Year-on-year compared with ONS PIPR per local authority each build; the index is not written when the median absolute disagreement exceeds 4 pp."
},
"notes": [
"4 period(s) are PROVISIONAL (2026M05..2026M08): the crawl has not finished observing them — recent listings are mostly still live and live pages are under-date…",
"The pipeline judged quarterly the resolvable grain for this area (posterior SE of the monthly move > 1 pp); the monthly series is stored but noisier. Read inc_…"
],
"source": "robosapien",
"cached": true,
"time_ms": 52.9
},
"credits_charged": 0
}A real response, captured from production and trimmed: arrays to three items, long strings shortened, volatile keys dropped.
Inputs
Arguments asking_rent_index_series takes
| Name | Type | Required | Description |
|---|---|---|---|
| area_code | string | No | Default: NATIONAL |
| area_type | string | No | One of: district, lad, nationalDefault: district |
| frequency | string | No | One of: monthly, quarterlyDefault: monthly |
| method | string | No | One of: hedonic_smoothed, hedonic_rawDefault: hedonic_smoothed |
| start | string | No | |
| end | string | No | |
| limit | integer | No | Default: 400 |
Response
What comes back
| Field | Type | Example |
|---|---|---|
| country | string | UK |
| query | object | |
| query.area_code | string | Lewisham |
| query.area_type | string | lad |
| query.frequency | string | monthly |
| query.method | string | hedonic_smoothed |
| query.limit | integer | 6 |
| data | object | |
| data.area | object | |
| data.area.scope | string | lad |
| data.area.area_key | string | c0694b59-04d1-48ab-9a4c-c4f9d7b74f60 |
| data.area.area_code | string | Lewisham |
| data.area.area_name | string | Lewisham |
| data.frequency | string | monthly |
| data.basis | string | Hedonic (mix-adjusted) index of ASKING rents fro |
| data.series | array | |
| data.series[].period | string | 2026M03 |
| data.series[].period_start | string | 2026-03-01 |
| data.series[].value | number | 110.37210808439843 |
| data.series[].lo | number | 109.16951798868122 |
| data.series[].hi | number | 111.58794567781428 |
| data.series[].se_pp | number | 0.8548678811047612 |
| data.series[].inc_se_pp | number | 1.0646344730950845 |
| data.series[].yoy_pct | number | 0.9445566632207525 |
| data.series[].n_obs | integer | 897 |
| data.series[].is_provisional | boolean | false |
| data.provenance | object | |
| data.provenance.source_table | string | marts_facts.listing_index |
| data.provenance.basis | string | asking_rent |
| data.provenance.method | string | hedonic_smoothed |
| data.provenance.pub_freq | string | quarterly |
| data.provenance.parent_key | string | NATIONAL |
| data.provenance.base_period | string | 2023 mean |
| data.provenance.n_obs_total | integer | 41207 |
| data.provenance.n_periods | integer | 6 |
| data.provenance.first_period | string | 2026M03 |
| data.provenance.last_period | string | 2026M08 |
| data.provenance.built_at | string | 2026-09-05T11:16:13.107592+00:00 |
| data.provenance.validation | string | Year-on-year compared with ONS PIPR per local au |
| data.notes | array | |
| data.source | string | robosapien |
| data.cached | boolean | true |
| data.time_ms | number | 52.9 |
| credits_charged | integer | 0 |
Fields observed in the example response above; a field the example did not exercise is not listed.
Usage
How to run asking_rent_index_series in your assistant
Ask your assistant in plain English, for example:
"Use the MarketCode tool asking_rent_index_series for <address or area>.
Show the result and the credits charged."
The arguments the assistant will send, for the example on this page:
{"area_code":"Lewisham","area_type":"lad","limit":6}The connect steps for Claude, ChatGPT, Codex, Cursor and Claude Code are on the MCP page.
Skills
Skills that use asking_rent_index_series
- Area insights: A market brief for any UK area: the published indices, volumes, listing stock, agent activity and auction outcomes, compared and ranked against neighbours.
- Deal analysis: A first-pass appraisal of a site or asset: plot utilisation, planning position, market evidence, value and a residual against the cost assumptions you supply.
Price and licence
What it costs, and where the data comes from
asking_rent_index_series is free over MCP and over REST, and the two surfaces share one credit balance. Free calls need a signed-in account or an API key and appear in your usage, but they never touch your balance.
Credits are granted on sign-up and bought in packs; the pricing page lists every call.
Computed by MarketCode from
- Office for National Statistics
Price Index of Private Rents and geography lookups
Open Government Licence v3 · UK
- Property portals
Sale and lettings listings
Collected from publicly marketed listings · Great Britain
How the model or index is built, and where it is weak, is on the methodology page.
Related
Tools used with asking_rent_index_series
- Commercial rent indexFree
commercial_rent_index_seriesCommercial RENT index from the VOA rating lists — FOUR points, one per list (2010 / 2017 / 2023 / 2026), each dated at that list's antecedent valuation date (2008-04-01, 2015-04-01, 2021-04-01, 2024-04-01), with the 2010 list = 100.Named in the description - Supply-side listing statisticsFree
listing_market_seriesMonthly supply-side statistics from portal listings for one area, channel and bedroom band: listings added and reduced, reduction share (the market-temperature signal), asking price or rent median and quartiles, £/m² where a floor area is stated, new-build share, agent concentration (HHI, top-3 share), and — on rent rows — gross yield on two bases (cell rent over cell price; per-listing rent over the unit's AVM value), and on sale rows the asking-to-sold ratio and days to completion on listings the registry matched to a sale.Named in the description - Asking-price index (portal listings)Free
asking_price_index_seriesHedonic ASKING-PRICE index for one postcode district, local authority or Great Britain, from portal listings (Rightmove ~95%), 2022M01 = 100, with 80% bands and posterior standard errors, smoothed toward the parent geography.Named in the description - Commercial capital indexFree
commercial_index_seriesRepeat-sales CAPITAL index for UK commercial property, quarterly, 1995Q1 = 100.Same category - Commercial capital and rent indices for a placeFree
commercial_marketThe commercial market for a sector and a place: the repeat-sales CAPITAL index, the VOA rating-list RENT index, and the rated stock standing in the authority with its hereditament count, total and median rateable value.Same category - Index forecast h1–h7 with bandsFree
market_forecastThe published house-price index forecast for a postcode district or local authority: the last SETTLED index point as the anchor, then up to seven forecast periods with `lo`/`hi` bands, plus the method and publication grain behind them. Seven is the horizon the index publishes — nothing beyond it is offered, and a forecast is a projection of the smoothed repeat-sales index, not a valuation of any property. UK only.Same category
Glossary
Terms used here
- Local authority district (LAD): The council area a property sits in: about 360 in Great Britain, the second geography MarketCode publishes indices and rankings for.
- Hedonic index: A price index that prices the attributes of each property (type, bedrooms, size, location) so that a change in what is on the market does not read as a change in prices; the method behind the asking indices.
FAQ
Questions about asking_rent_index_series
How much does `asking_rent_index_series` cost?
+
asking_rent_index_series is free over MCP and over REST, and the two surfaces share one credit balance. Free calls need a signed-in account or an API key and appear in your usage, but they never touch your balance.
Which assistants can run `asking_rent_index_series`?
+
Any MCP client: Claude (claude.ai, Claude Desktop, Claude Code), ChatGPT in developer mode, Codex and Cursor, each documented on the MCP page. You sign in with your MarketCode account over OAuth; there is no key to paste, and the connection is read-only.
Where does the data come from?
+
Computed by MarketCode from Office for National Statistics price index of private rents and geography lookups and Property portals listings. Coverage is Great Britain. The methodology page describes how the model or index is built.
Does `asking_rent_index_series` change anything?
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No. The tool is annotated read-only on the server, so it never writes to your data or ours and an assistant can call it without a confirmation step.
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