State Registration (IE) Lookup by CNPJ
A company's State Registration (Inscrição Estadual, IE) is its entry in the ICMS taxpayer registry of its Brazilian state - any business that issues goods invoices needs one. CNPJAPI looks up a CNPJ's IE straight from the official source, the State Revenue offices' (SEFAZ) taxpayer registry, and without you needing your own digital certificate.
The problem
- The federal Receita Federal database (and the APIs that only mirror it, such as ReceitaWS) does not carry the State Registration - the IE is state-level, not federal.
- Integrating with SEFAZ yourself requires a digital certificate and a per-state implementation - costly and slow.
- Sites that "look up IE" usually scrape the SEFAZ portals: they break when a portal changes, hit captchas, and offer no stable API to automate.
How the API solves it
One call per CNPJ returns the State Registration from the official source:
- Official SEFAZ source (taxpayer registry), not scraping
- No certificate of yours: CNPJAPI bridges to SEFAZ; you use just the API key
- 26 states covered (all but Maranhão): AC, AL, AM, AP, BA, CE, DF, ES, GO, MG, MS, MT, PA, PB, PE, PI, PR, RJ, RN, RO, RR, RS, SC, SE, SP, TO
- By state or a nationwide sweep in a single call
- Status (active or cancelled), taxpayer type (ICMS taxpayer, exempt or non-taxpayer) and the legal name as held in the state registry
- REST API with the same key as the CNPJ lookup; combine both with
?incluir=ie
See the full contract and the live availability by state.
Official source vs scraping
| CNPJAPI (official source) | Portal scrapers | |
|---|---|---|
| Origin | Official SEFAZ web service | Portal HTML, subject to change |
| Stability | Versioned, stable contract | Breaks when the portal changes |
| Captcha | No | Frequent |
| Automation | REST API with a key | Fragile or nonexistent |
| Coverage | 26 states (all but MA) | Varies per site |
What changes in practice
The difference between IE lookup APIs is not only the source of the data. It is how each one charges for the nationwide sweep, and what happens to the credit you bought.
| CNPJAPI | Other IE lookup APIs | |
|---|---|---|
| Nationwide sweep (all states) | Flat rate, no matter how many states answer | Charged per state queried: a single sweep can become 27 charges |
| Lookup with a known state | One charge | One charge |
| Purchased credit | Never expires | Usually expires in a year, or is reset every month |
Based on an October 2026 review of the public pricing pages of IE lookup API services.
An API alternative to SINTEGRA: IE lookup by CNPJ
SINTEGRA (Brazil's integrated system for interstate ICMS operations) is the free public service that aggregates the state tax authorities' (SEFAZ) ICMS taxpayer registries and lets you check, by CNPJ, whether a company's State Registration (IE) exists and its status. For a one-off lookup it does the job - but it's manual, one portal per state, with captchas and no API to automate.
CNPJAPI queries the same official SEFAZ ICMS taxpayer registry, through a stable REST API: one call per CNPJ, by state or as a nationwide sweep, with no captcha and no portal-by-portal navigation. It's SINTEGRA for teams that need to automate - integrate into an ERP, validate records in bulk or query at scale.
Some services advertise "27 states", but via portal scraping. CNPJAPI covers 26 of the 27 states straight from the official SEFAZ web service - the only one out is Maranhão, which SEFAZ-MA itself does not make available for registry lookup.
CNPJAPI is not SINTEGRA and is not affiliated with it; the data comes from the same source - the state tax authorities' ICMS taxpayer registries.
FAQ
Does Receita Federal (or ReceitaWS) return the State Registration? No. The IE is a state-level (ICMS) record; the federal registry does not include it. It comes from each state's SEFAZ.
How do I look up a CNPJ's IE?
Call GET /consulta/ie/{cnpj}?uf=SP with your API key, or omit the state to sweep the 26 covered states in one call.
Does SINTEGRA have an API? SINTEGRA itself is a manual lookup - one portal per state, with captcha - and exposes no unified official API for automation. CNPJAPI queries the same official SEFAZ ICMS taxpayer registry through a REST API: by CNPJ, by state or in a nationwide sweep.
How do I look up State Registration across several states via API? Each SEFAZ has its own web service and there is no single official API. CNPJAPI unifies 26 of the 27 states (all except Maranhão, which SEFAZ-MA itself does not offer) in one REST API: query by state or run the nationwide sweep in a single call.
Do I need a digital certificate? No. CNPJAPI already runs the official SEFAZ integration; you query with just the API key.
Is CNPJAPI's IE lookup a SINTEGRA? The data is the same you'd find on SINTEGRA - the state SEFAZ ICMS taxpayer registry - but CNPJAPI delivers it through a REST API, to automate by CNPJ, by state or nationwide, with no captcha. CNPJAPI is not SINTEGRA and is not affiliated with it.
Where to start
- Generate your API key at https://app.cnpjapi.com.br. Every registered plan includes a monthly IE quota - the free plan too - plus top-up credits for volume.
- Call
GET /consulta/ie/{cnpj}?uf=SP, or omit the state for the nationwide sweep (see the guides). - Need the registration data alongside? Use
GET /{cnpj}?incluir=ie.
Create your account and look up State Registration from the official source in minutes.