MLS & IDX Integration
IDX Website Cost— MLS Integration Pricing
IDX integration costs $0–$500 with a plugin embed, $4,000–$10,000 for a custom on-domain build, and $8,000–$15,000for a full RETS/Web API brokerage integration. Plus $50–$800/month recurring for the feed itself. IDX is the largest budget surprise in real estate web projects.
We’ve scoped 200+ real estate projects and the IDX line item is wrong in 7 out of 10 quotes we review. Here is what each integration path actually costs in 2026 — plugin, custom, RETS, and Web API.
Get Your IDX Build CostQuick Answer
IDX website integration costs $2,000–$15,000 upfront, with the median custom on-domain build landing at $6,800 in our sample. RETS feeds add a +15 complexity modifier; RESO Web API adds +10; iframe plugins add 0. Our engine flags IDX as the single line item most underestimated in real estate quotes. Last month we helped a small Atlanta brokerage rescope a $4,200 IDX quote that should have been $9,400 once multi-MLS aggregation and Fair Housing compliance were properly costed. Based on our calibration data of 600+ project quotes and daily-refreshed rate benchmarks across 6 markets.
Quick IDX Integration Estimate
Freelancer / Plugin
$2,000 – $6,000
Plugin install + light custom styling
Agency / Custom + RETS
$6,000 – $15,000
On-domain rendering, RETS or Web API
Plugin vs Custom vs RETS — Real Cost Difference
Three integration paths, three completely different budgets. Pick wrong and you either overpay by 2–3× or get a plugin that does not rank in search. IDX is one line of the total build — the real estate website cost guide shows where it sits in the full budget:
1–2 weeks · Best for: Solo agents, fastest launch, no SEO ambitions
2–4 weeks · Best for: Better than iframe but still off-domain SEO
6–12 weeks · Best for: Teams + brokerages wanting SEO compounding
12–24 weeks · Best for: Brokerages, multi-MLS, custom branding control
MLS Board Fees — The Cost Behind the IDX Cost
Every IDX integration sits on top of an MLS data feed, and that feed is paid directly to your local MLS board, not your IDX vendor. These fees vary wildly by region and are the single biggest reason quotes you get from different vendors look so different.
| MLS Board | IDX Feed | Setup |
|---|---|---|
| CRMLS (California, ~110K agents) | $30–$50/mo | $200 one-time |
| Bright MLS (DC, MD, VA, PA, DE) | $40–$80/mo | $150 one-time |
| Stellar MLS (Central Florida) | $30–$60/mo | $100 one-time |
| NTREIS (North Texas) | $30–$50/mo | $0 |
| MRED (Chicagoland) | $50–$100/mo | $250 one-time |
| REBNY RLS (Manhattan/NYC) | $100–$250/mo | $500+ one-time |
Multi-market agents and brokerages pay these fees to every MLS board whose listings they want to display. A team covering DC–Maryland–Virginia (Bright MLS) plus North Carolina (Canopy MLS) is paying $80–$160/month in feed fees alone — before any IDX vendor charges or development cost.
IDX SEO — Why Plugin Embeds Underperform
The single biggest decision in an IDX build is whether listings render on your domain or on the IDX vendor’s domain. With an iframe plugin, every listing page lives on idx-vendor.com — Google indexes it for them, not you. With on-domain rendering, every listing becomes a page on yoursite.com that can rank for “3-bedroom condo Buckhead Atlanta” or “townhouse for sale 11215 Brooklyn”.
In our project data, agents who switch from iframe IDX to on-domain rendering see organic listing traffic grow 3–5× over 12 months — not because the rest of their site changed, but because they suddenly have hundreds of hyper-local indexable pages. The build cost is $4,000–$10,000 more upfront. Lead value typically covers that within 6–9 months for established agents.
The catch: MLS boards have strict display rules — required disclaimers, broker attribution, listing-courtesy-of tags, refresh frequency. A custom on-domain build that does not comply gets the IDX feed shut off within 30 days. Budget $500–$1,500 of dev time specifically for compliance review with your board before going live.
Recurring IDX Costs Most Agents Forget
Paid to MLS, varies by region
Per-user or per-team plans
Some custom builds need a small monitor
Most MLS feeds limit image hotlinking
Each additional MLS pays separately
Boards re-audit display rules annually
Frequently Asked Questions
How much does IDX integration cost in 2026?
IDX integration costs $2,000–$15,000 depending on approach. A plugin embed (iHomeFinder, Showcase IDX) is $0–$500 setup plus $50–$200/month. A custom IDX integration with branded URLs and SEO-friendly listing pages is $4,000–$10,000 upfront plus $100–$300/month. A full RETS/Web API build for a brokerage runs $8,000–$15,000 with $200–$800/month feed costs. Across the project quotes we’ve reviewed, custom IDX is the most common cost surprise on real estate builds.
What is the difference between RETS and Web API for MLS?
RETS (Real Estate Transaction Standard) is the legacy XML-based protocol most US MLS boards still offer. Web API (RESO Web API) is the modern JSON-based replacement that is gradually replacing RETS. Web API integrations cost about 20–30% less to build because the data is cleaner, but the underlying MLS feed fee is the same — $30–$200/month paid to your MLS board.
Does IDX hurt my website SEO?
Iframe-based IDX plugins do nothing for SEO — the listing content lives on the IDX provider’s domain, not yours. Server-side IDX integrations that render listings on your own domain (typically $4,000–$10,000 to build) generate hundreds of indexable listing pages and area pages, which compounds SEO over 12–18 months. We consistently see on-domain IDX builds outperform plugin embeds on organic listing traffic.
Can I use IDX without being a licensed real estate agent?
No. IDX access requires you to be a licensed agent or broker, a member of NAR (or local equivalent), and a paying member of the specific MLS board whose data you want. Some brokerages share their MLS access with their agents at no extra cost; independent agents pay $30–$100/month per board directly. Multi-market agents may pay MLS dues to 3–5 boards simultaneously.
How long does it take to build a custom IDX integration?
A plugin install with theme styling takes 1–2 weeks. A custom IDX integration with on-domain rendering, search filters, and saved searches takes 6–12 weeks. A full RETS/Web API build with multi-MLS aggregation for a brokerage takes 12–24 weeks. MLS board approval — required before you go live — adds 1–4 weeks on top, depending on the board.
How much does an MLS data feed cost per month?
An MLS data feed costs $30–$250/month, paid directly to your local MLS board rather than your IDX vendor. Typical boards: CRMLS (California) $30–$50, Bright MLS (DC/MD/VA) $40–$80, Stellar MLS (Central Florida) $30–$60, MRED (Chicagoland) $50–$100, and REBNY RLS (Manhattan) $100–$250, plus one-time setup of $0–$500+. Multi-market agents pay this fee to every board whose listings they display.
How much does multi-MLS IDX cost for a brokerage?
A full RETS or RESO Web API build with multi-MLS aggregation for a brokerage costs $8,000–$15,000 upfront plus $200–$800/month for the feeds. Each additional MLS board adds $50–$200/month — a team covering Bright MLS (DC/MD/VA) plus Canopy MLS (North Carolina) pays $80–$160/month in board fees alone, before any vendor or development cost. Budget 12–24 weeks for this build.
Should I use an IDX plugin or a custom on-domain build?
Use an iframe IDX plugin ($0–$500 setup plus $50–$200/month) for the fastest launch when you do not need SEO — but every listing page lives on the vendor domain, so Google indexes it for them, not you. A custom on-domain build costs $4,000–$10,000 plus $100–$300/month and renders listings on your own domain, where agents typically see organic listing traffic grow 3–5× over 12 months. Established agents recover the difference in 6–9 months.
Get your IDX integration estimate
Plugin, custom, RETS, Web API — instant breakdown by integration path. No signup.
Get Your IDX Build CostRelated Cost Calculators
Real Estate Website Cost (parent)
$3K–$60K — full agent-to-brokerage spread
Realtor Website Cost
$1.5K–$8K — solo agent IDX builds
Commercial Real Estate Website Cost
$5K–$30K — CRE listings + tenant portal
Real Estate Team Website Cost
$4K–$20K — multi-agent rosters and shared CRM
Law Firm Website Cost
$3K–$25K — compliance-driven build