Zillapi vs ATTOM Data: which property API is right for you in 2026

Zillow API vs ATTOM Data Solutions. Pricing, coverage, code, and the right pick when you need a Zillow Data API or public records in 2026.

By Zillapi May 2, 2026

ATTOM Data is enterprise property infrastructure. Zillapi is a Zillow API you can integrate this afternoon.

They solve different problems. ATTOM covers 158 million U.S. properties with deed records, mortgage filings, ownership history, tax assessments, and an AVM, per their property data page. Zillapi covers Zillow’s listing graph: active for-sale, for-rent, recently sold, photos, price history, and the Zestimate.

If you need public records depth and your business has the budget, pick ATTOM. If you need Zillow’s listing data with an API key you can issue in 60 seconds, pick Zillapi.

TL;DR

	Zillapi	ATTOM Data
Pricing	$5/mo for 1,000 credits, scales to $99+	From ~$95/mo entry, custom contracts typically $1k+/mo (per public pricing as of May 2026)
Free tier	100 credits one-time at signup	Trial via sales
Signup speed	Self-serve, under 60 seconds	Sales call, then contract
Coverage	Zillow listing graph (~160M parcels)	158M+ U.S. properties, public records depth
Output formats	JSON, CSV, NDJSON	JSON, XML, bulk file delivery
Webhooks	First-class, HMAC-signed	Not core to product
OpenAPI	`/openapi.json` covers every endpoint	Yes, swagger documented
Zestimate	Yes, via `/v1/properties/{zpid}/zestimate`	No, ships its own AVM instead
Best for	Listing data, fast integration, indie devs and startups	Enterprise PropTech, mortgage, insurance

What is ATTOM Data?

ATTOM is one of the largest U.S. property-data providers. Their data warehouse covers more than 158 million U.S. residential and commercial properties with 9,000+ fields and 70 billion rows, per their own page.

Coverage includes deed and mortgage filings, ownership history, tax assessments, school catchments, neighborhood metrics, environmental hazards, and an AVM. ATTOM customers are typically PropTech platforms, mortgage origination, insurance underwriting, and government agencies.

The ATTOM API is well documented. The data is licensed. The contracts are real.

The trade-offs are price and pace. Plan on a sales cycle, an MSA, and a per-record or seat-based contract. Their pricing model is per API report rather than per call.

What is Zillapi?

Zillapi is a self-serve Zillow Data API.

We focus on Zillow’s listing graph. Active for-sale and for-rent listings. Recently sold homes. Photos. Price history. Tax history. Schools. Agents. The Zestimate. One API key. One base URL. $5/mo to start. A stable v1 contract.

We do not compete with ATTOM on public records depth. We make Zillow’s surface usable by an engineer in 60 seconds.

Side-by-side: making the same call

Same task, both providers. Get one property record.

Zillapi:

curl https://api.zillapi.com/v1/properties/11026031 \
  -H "Authorization: Bearer $ZILLAPI_KEY"

Returns Zillow’s view of the property. List price, Zestimate, photos, beds, baths, year built, MLS attributes via /facts.

ATTOM, hitting the property detail endpoint by address:

curl "https://api.gateway.attomdata.com/propertyapi/v1.0.0/property/detail?address1=17+Zelma+Dr&address2=Greenville,+SC" \
  -H "apikey: $ATTOM_KEY" \
  -H "accept: application/json"

Returns the deed-and-records view. Owner name, last sale, tax assessment, AVM estimate, lot dimensions. Different shape, different mental model.

The two responses are complementary. ATTOM tells you who owns the parcel and what it sold for last. Zillapi tells you what the listing looks like on Zillow today and what the Zestimate is.

Pricing breakdown

ATTOM, per public references as of May 2026:

Entry tier API: starts around $95/mo for low-volume access.
Production deployments: typically $1k+ per month, billed per API report.
The per-report rate scales down with volume. $1,000/mo for 100,000 reports is roughly $0.01 per report at that tier.
Bulk file delivery and ATTOM Cloud pricing are quoted custom by sales.

Zillapi, per public pricing on zillapi.com as of May 2026:

Free at signup: 100 credits.
Hacker: $5/mo, 1,000 credits.
Pro: $29/mo, 10,000 credits.
Scale: $99/mo, 50,000 credits.
Most endpoints cost 1 credit. Heavy listing pages and async jobs cost more, documented per endpoint in /openapi.json.

For a typical indie or startup workload doing a few thousand to a few tens of thousands of property reads per month, Zillapi is materially cheaper. For a national mortgage workflow that needs every parcel in a region with deed and tax history, ATTOM is the only option in the comparison that ships that shape of data at all.

Zestimate vs ATTOM AVM

If you need a property valuation, the model matters.

The Zestimate reports a 1.9% nationwide median error rate for on-market homes and around 6.9% for off-market homes, per Zillow’s published benchmarks. ATTOM’s AVM reports a median absolute error around 6%, per ATTOM’s own AVM materials.

The Zestimate is tuned for consumer listing flow. ATTOM’s AVM is tuned for enterprise and lender-grade applications.

Zillapi exposes the Zestimate. ATTOM exposes their AVM. If you specifically need Zillow’s number, that is us. If you need a licensed AVM with an enterprise SLA for an underwriting decision, that is them.

When to choose ATTOM

Pick ATTOM when you need public records depth.

Owner names. Mortgage filings. Lien data. Transfer history. Parcel boundaries. ATTOM ships those as licensed records with a clear data lineage.

Pick ATTOM for regulated workflows where licensing matters, like mortgage origination, insurance underwriting, or AVM-driven offers. Bulk-file delivery is genuinely useful when you need to load a county or a whole state into a warehouse.

If you are building HouseCanary-class analytics, a national title platform, lending tooling, or a multi-state PropTech that needs deed records across every county, ATTOM is on your shortlist for good reasons.

When to choose Zillapi

Pick Zillapi when you want Zillow data specifically.

Zestimates. Listing photos. Listing descriptions. Price history. Days-on-market signals. Agents. Open-house schedules. The fields a consumer-facing real-estate flow actually needs.

We are the right pick for indie devs, side projects, lead-gen tools, real-estate-investor tooling, AI agents that need property context, and teams who want to validate a feature before paying enterprise prices.

Field projection (?fields=zpid,price,zestimate), CSV/NDJSON output, and async batches up to 500 entries per job make us a fit for analytics work without enterprise overhead.

The honest case against Zillapi

We are not a substitute for ATTOM if you need public records.

We do not expose owner names, deed records, mortgage filings, lien records, or parcel boundaries. That is not the data we are bringing to you. If your product needs those fields, you need ATTOM (or a competitor like CoreLogic, Black Knight, or Estated) and you should not pretend our Zillow wrapper covers it.

We are not a licensed dataset for regulated decisions. A mortgage AVM-driven offer or an insurance underwriting workflow needs licensed data with contractual lineage. The Zestimate is exposed by Zillow on the consumer site. We pass it through. Neither of us is positioning that as a regulated AVM you can build a lending workflow around.

We do not do bulk file delivery to S3 or GCS at the indie tier. If you want a state loaded into your warehouse on a schedule, that is ATTOM’s home turf.

Many teams use both products. ATTOM for the parcel-of-record (owner, last sale, tax, deed, mortgage). Zillapi for the listing-of-record (list price, Zestimate, photos, agents). Match by address or zpid.

FAQ

Does ATTOM have Zestimates?

No. ATTOM ships its own AVM, not Zillow’s Zestimate. Per ATTOM’s own materials, their AVM has a median absolute error around 6%, while Zillow’s Zestimate reports a 1.9% nationwide median error rate for on-market homes. Different models, different inputs, different licensing. If you need the Zestimate specifically, ATTOM does not have it.

How much does ATTOM cost?

ATTOM’s API starts around $95/mo for entry plans per public references as of May 2026, but the real-world price depends on volume. ATTOM bills per API report rather than per call, so a deployment doing $1,000/mo for 100,000 reports works out to about $0.10 per report. Most production deployments price out into the $1k+ per month range.

How fast can I integrate ATTOM?

Plan on a sales conversation, an MSA, and a few weeks before the contract is signed and the keys are issued. ATTOM is enterprise sales. If your team needs to ship a feature this sprint, that is the wrong shape.

Why would I pick Zillapi over ATTOM?

Speed and price at the indie and startup end. Zillapi is self-serve, $5/mo to start, and you make your first call in 60 seconds. ATTOM is the right choice when you need owner names, deed records, mortgage filings, and a licensed dataset for a regulated workflow. Different problems.

Can I use both?

Yes. Many teams stitch ATTOM and Zillapi together. ATTOM for public records and AVM, Zillapi for the Zillow listing surface (Zestimate, photos, list prices, agents). Match by address or zpid and dedupe on your side.

Does Zillapi cover all 158 million properties ATTOM covers?

Not as a parcel database. Zillapi exposes Zillow’s listing graph, which is around 160M parcels but optimized for residential listing flow rather than every commercial parcel and tax record in the country. If your workflow needs every commercial parcel, talk to ATTOM.

Verdict

If you are building a regulated real-estate workflow that needs licensed public records and your roadmap can absorb enterprise procurement, ATTOM Data is the right call.

If you are building anything that needs Zillow’s listing surface and wants to be in production this afternoon, start with the Zillapi quickstart. First call in 60 seconds. No sales call. No MSA.

Zillapi is an independent service and is not affiliated with, endorsed by, or sponsored by Zillow Group, Inc. “Zillow” and “Zestimate” are registered trademarks of Zillow Group, Inc. Use of those marks on this site is descriptive (nominative fair use). Read our full trademark posture.

Frequently asked questions

Does ATTOM have Zestimates?: No. ATTOM ships its own AVM, not Zillow's Zestimate. Per ATTOM's own materials, their AVM has a median absolute error around 6%, while Zillow's Zestimate reports a 1.9% nationwide median error rate for on-market homes. Different models, different inputs, different licensing. If you need the Zestimate specifically, ATTOM does not have it.
How much does ATTOM cost?: ATTOM's API starts around $95/mo for entry plans per public references as of May 2026, but the real-world price depends on volume. ATTOM bills per API report rather than per call, so a deployment doing $1,000/mo for 100,000 reports works out to about $0.10 per report. Most production deployments price out into the $1k+ per month range.
How fast can I integrate ATTOM?: Plan on a sales conversation, an MSA, and a few weeks before the contract is signed and the keys are issued. ATTOM is enterprise sales. If your team needs to ship a feature this sprint, that is the wrong shape.
Why would I pick Zillapi over ATTOM?: Speed and price at the indie and startup end. Zillapi is self-serve, $5/mo to start, and you make your first call in 60 seconds. ATTOM is the right choice when you need owner names, deed records, mortgage filings, and a licensed dataset for a regulated workflow. Different problems.
Can I use both?: Yes. Many teams stitch ATTOM and Zillapi together. ATTOM for public records and AVM, Zillapi for the Zillow listing surface (Zestimate, photos, list prices, agents). Match by address or zpid and dedupe on your side.
Does Zillapi cover all 158 million properties ATTOM covers?: Not as a parcel database. Zillapi exposes Zillow's listing graph, which is around 160M parcels but optimized for residential listing flow rather than every commercial parcel and tax record in the country. If your workflow needs every commercial parcel, talk to ATTOM.