Question 1

Where does the data come from?

Accepted Answer

From the Iowa Department of Inspections, Appeals, and Licensing (DIAL), Building & Construction Division: the open-data set 'Active Iowa Construction Contractor Registrations' (data.iowa.gov dataset 1052), published under CC BY 4.0 and refreshed weekly. The actor downloads it on every run.

Question 2

Does it include phone and email?

Accepted Answer

Yes. DIAL removed phone and email from its public file on 2026-11-03. This actor matches each registration, by its DIAL registration number, to DIAL's 2026-10-14 file, the last edition that carried them: phone on 97.5% and email on 95.5% of active registrations (2026-11-05). Contractors who registered after 2026-10-14 have none. If DIAL publishes the columns again, the current values are used automatically.

Question 3

Is this a licence or a registration?

Accepted Answer

A registration. Iowa does not license general contractors at state level; anyone earning at least $2,000 a year from construction in Iowa must register with DIAL and renew annually. Trades such as electrical and plumbing also need separate DIAL trade licences, which this file does not cover.

Question 4

How many contractors are there?

Accepted Answer

18,000 active registrations on 2026-10-07. Largest trades: Residential Remodelers 3,397, All Other Specialty Trade 1,796, Electrical 1,727, Plumbing/Heating & A/C 1,436, Roofing 880. Largest counties: Polk 2,437, Linn 1,071, Johnson 553, Scott 496.

Question 5

Does it include out-of-state contractors?

Accepted Answer

Yes, 4,057 of the 18,000 (22.5%) have a mailing address outside Iowa, most often Nebraska (887), Minnesota (527) and Illinois (435). Tick 'Iowa mailing addresses only' to drop them. DIAL leaves county blank for most of them, so a county filter returns Iowa addresses only.

Question 6

How do I name a trade?

Accepted Answer

With a word from the activity label, matched at the start of a word ('roofing', 'electrical', 'remodelers'), or a NAICS code ('238160') or prefix ('2382' for every specialty trade). DIAL uses 32 activities: 230000 Other/Undefined plus the NAICS codes from 236115 New Single-Family Housing Construction to 238990 All Other Specialty Trade Contractors; a value that matches none of them is dropped and logged.

Question 7

Does it include expired registrations?

Accepted Answer

No. DIAL's file holds only registrations with status Registered and an expiry date on or after the refresh date, so every row reads status 'Registered'.

Question 8

How am I charged?

Accepted Answer

$0.004 per registration returned. The default run returns 500 rows ($2.00); the whole state was 18,257 rows ($73.03) on 2026-11-05. Rows explaining an outage or an unrecognised filter are free.

Field	Type
`license_number`	string\|null
`business_name`	string\|null
`person_name`	string\|null
`first_name`	string\|null
`last_name`	string\|null
`phone`	string\|null
`email`	string\|null
`address`	string\|null
`city`	string\|null
`address_state`	string\|null
`zip_code`	string\|null
`county`	string\|null
`naics_code`	string\|null
`primary_activity`	string\|null
`status`	string\|null
`issue_date`	string\|null
`expiration_date`	string\|null
`license_type`	string\|null
`state`	string\|null
`notice`	string\|null
`notice_type`	string\|null
`source_url`	string\|null

Field	Type	Req	Default	Description
`trade`	string	no	—	A word from DIAL's primary-activity label ('roofing', 'electrical', 'plumbing', 'remodelers') — matches at the start of a word — or a NAICS code ('238160') or code prefix ('2382' = every specialty trade). A value that matches none of the 32 activities is dropped and logged.
`trades`	array	no	`[]`	Several trades in ONE run, e.g. roofing and siding. Combined with 'Trade' if you fill both.
`county`	string	no	—	Iowa county, e.g. 'Polk', 'Linn County', 'obrien'. DIAL fills county for Iowa addresses only. An unrecognised county is dropped and logged.
`counties`	array	no	`[]`	Several counties in ONE run. Combined with 'County' if you fill both.
`city`	string	no	—	Mailing city, exact match ignoring case and punctuation, e.g. 'Des Moines'.
`cities`	array	no	`[]`	Several cities in ONE run.
`zipCode`	string	no	—	5-digit mailing ZIP, e.g. '50309'.
`zipCodes`	array	no	`[]`	Several ZIP codes in ONE run.
`nameFilter`	string	no	—	Case-insensitive text found in the business name or the registrant's first/last name, e.g. 'roofing llc' or 'smith'.
`nameFilters`	array	no	`[]`	Several names in ONE run; a registration matching any of them is returned once.
`iowaAddressesOnly`	boolean	no	`false`	Registrants from any state can work in Iowa: 4,057 of 18,000 (22.5%, 2026-10-07) have an out-of-state mailing address. Tick to drop them.
`maxResults`	integer	no	`500`	Cap on registrations returned for the WHOLE run (this is an export; the cap is your spend control). The full roster was 18,000 on 2026-10-07 — set 100000 to take everything that matches.
`proxyConfiguration`	object	no	`{"useApifyProxy":false}`	Optional. data.iowa.gov answers direct requests; enable a proxy only if a run returns a 'blocked' notice.