Title: CompanyStack – UK Company Search & Directory
Author: CompanyStack
Published: October 12, 2026
Last modified: October 12, 2026
---
Search plugins
# CompanyStack – UK Company Search & Directory
By [CompanyStack](https://profiles.wordpress.org/swilson23/)
[Download](https://downloads.wordpress.org/plugin/companystack.1.2.0.zip)
* [Details](https://wordpress.org/plugins/companystack/#description)
* [Reviews](https://wordpress.org/plugins/companystack/#reviews)
* [Installation](https://wordpress.org/plugins/companystack/#installation)
* [Development](https://wordpress.org/plugins/companystack/#developers)
[Support](https://wordpress.org/support/plugin/companystack/)
## Description
Customers type the first few letters of their company name, pick it from the list,
and the company number and registered office address are filled in for them. No
more mistyped company numbers on B2B orders, trade account applications or quote
requests.
The plugin works in the WooCommerce checkout, in Contact Form 7, WPForms and Gravity
Forms, and in any HTML form, and it has a ready-made Company Lookup Form of its
own in six designs. It also adds company profile cards, an “Active UK company” status
badge and a business directory, each as a block and as a shortcode.
Company data comes from the Companies House register, as held and kept up to date
by the CompanyStack API. CompanyStack is an independent service: it is not affiliated
with, or endorsed by, Companies House.
**What you get**
* **Company Lookup Form.** A finished form you can drop on any page: the visitor
types a company name, picks it, and the company number, address, town and postcode
are filled in. Choose which fields show and what they are called. An optional
send button emails what the visitor entered to the site administrator; nothing
is stored.
* **Six designs, fully customisable.** Clean, Soft, Underline, Card, Compact inline
and Inherit theme. Set a site-wide design, accent colour, corner radius, field
size and font under Settings › CompanyStack › Appearance, with a live preview
and a warning when colours fail WCAG AA contrast. Every block has its own design
controls, and the blocks support the editor’s own colour, typography, spacing
and border settings where they apply.
* **Looks right in your theme.** By default the plugin inherits your theme’s font
and text colour and picks an accent from its palette. It follows dark themes,
right-to-left languages, high-contrast mode, 200% zoom and reduced-motion settings,
with visible focus rings and 44-pixel touch targets. No external fonts or files
are loaded.
* **Company autocomplete with form auto-fill.** Works with the Company Search block
or `[companystack_search]`, with Contact Form 7, WPForms and Gravity Forms (add
a CSS class to your fields), and with any HTML form (data attributes). In those
forms only the suggestions list is styled, never the form itself.
* **WooCommerce B2B checkout.** The checkout Company field suggests UK companies
and fills in the address. An optional “Company registration number” field is
filled automatically, validated and saved with the order. Works with both the
Checkout block and the classic checkout, and is compatible with High-Performance
Order Storage.
* **Company profile card.** Status, company number, type, incorporation date, registered
office, nature of business (SIC codes) and accounts and confirmation-statement
due dates, with overdue warnings.
* **“Active UK company” status badge.** Show visitors that your business (or a
supplier, member or client) is registered and active at Companies House, linked
to the official record. The badge hides itself automatically if the company stops
being active. It shows the register entry only: it does not verify who runs the
website it appears on.
* **UK business directory.** List companies by SIC code, postcode area or district(
for example NE or M1), town or name, with an optional visitor search form. Ideal
for trade associations, local business listings and industry directories.
* **Ready-made patterns.** “Company lookup form”, “Company profile card”, “Company
status badge” and “Business directory” are in the block inserter under CompanyStack,
and one click on the settings screen makes a draft page from any of them.
Each feature is available as a block and as a shortcode.
**Built to be safe and light**
* Your API key stays on your server. Browsers only talk to your own site’s REST
API, which calls CompanyStack server-side.
* Visitor searches are protected by a nonce and a per-visitor rate limit, so nobody
can burn through your allowance.
* Answers are cached (one day by default) to keep pages fast and API usage low.
* No jQuery, no tracking of you or your visitors, no upsell notices (one welcome
message on the Plugins screen, which you can dismiss), no front-end credit link
unless you switch it on.
* Blocks are built with core WordPress components; there is no heavy JavaScript
bundle.
**About the CompanyStack service**
This plugin is an interface to the CompanyStack API (see “External services” below),
which does the work of searching and serving Companies House records. You need a
CompanyStack API key. The free plan needs no payment card and covers company search,
autocomplete (up to 5 suggestions), company profiles, badges and directories of
up to 10 results. Paid plans raise the daily request limits and allow larger, paginated
directories. Every feature of the plugin works on the free plan; see [companystack.co.uk/pricing](https://companystack.co.uk/pricing)
for limits and prices.
### External services
This plugin connects to the **CompanyStack API** at `https://api.companystack.co.
uk`, operated by CompanyStack, to look up UK company information derived from the
public Companies House register. It cannot work without this service.
**When requests are made**
* When a visitor types at least two characters into a CompanyStack company search
field (including the WooCommerce checkout Company field when enabled) and pauses:
the typed text is sent to find matching companies.
* When a visitor chooses a company from the suggestions: its company number is
sent to fetch the full record used to fill the form.
* When a page containing a company card, status badge or directory block or shortcode
is displayed and the answer is not already cached: the company number, or the
directory filters (SIC code, postcode, town, name and status, including any search
a visitor enters in the directory form), are sent.
* When an administrator clicks “Test connection” on the settings screen: two sample
searches (for the word “TESCO”) are sent to check the key and see what its plan
allows.
**What is sent**
Only the search text, company number or directory filters described above, together
with your site’s CompanyStack API key (to identify your account) and a user-agent
string naming this plugin and its version. Requests are made from your web server;
visitors’ IP addresses, cookies and other form fields are **not** sent. Nothing
is sent until an API key has been saved, and the plugin does not collect usage statistics.
The Company Lookup Form’s optional send button does **not** send anything to CompanyStack:
what the visitor entered (including a name and email address, if you switch those
fields on) goes to your own site, which emails it to the site administrator. The
appearance settings and the live preview make no requests at all; the preview uses
invented sample data.
Links to companystack.co.uk on the plugin’s settings screen carry the tags `utm_source
=wordpress-plugin` and `utm_medium`, which tell CompanyStack only that a visit came
from the plugin. They contain nothing about your site, and nothing is sent unless
you click a link.
* CompanyStack terms of service: https://companystack.co.uk/terms
* CompanyStack privacy policy: https://companystack.co.uk/privacy
Company data originates from Companies House and is provided under the Open Government
Licence v3.0. Company pages link to the official Companies House service (find-and-
update.company-information.service.gov.uk); those links are ordinary hyperlinks
and send nothing unless a visitor clicks them.
## Screenshots
[⌊Company Lookup Form (Card design) with the suggestions list open.⌉⌊Company Lookup
Form (Card design) with the suggestions list open.⌉[
Company Lookup Form (Card design) with the suggestions list open.
[⌊The six form designs: Clean, Soft, Underline, Card, Compact inline and Inherit
theme.⌉⌊The six form designs: Clean, Soft, Underline, Card, Compact inline and Inherit
theme.⌉[
The six form designs: Clean, Soft, Underline, Card, Compact inline and Inherit theme.
[⌊Settings › CompanyStack › Appearance, with the live preview.⌉⌊Settings › CompanyStack›
Appearance, with the live preview.⌉[
Settings › CompanyStack › Appearance, with the live preview.
[⌊WooCommerce Checkout block: the Company field suggesting UK companies.⌉⌊WooCommerce
Checkout block: the Company field suggesting UK companies.⌉[
WooCommerce Checkout block: the Company field suggesting UK companies.
[⌊Contact Form 7 form filled in after choosing a company from the suggestions.⌉⌊
Contact Form 7 form filled in after choosing a company from the suggestions.⌉[
Contact Form 7 form filled in after choosing a company from the suggestions.
[⌊Company profile card and "Active UK company" status badges.⌉⌊Company profile card
and "Active UK company" status badges.⌉[
Company profile card and “Active UK company” status badges.
[⌊UK business directory with the visitor search form.⌉⌊UK business directory with
the visitor search form.⌉[
UK business directory with the visitor search form.
[⌊Settings › CompanyStack, with the getting started panel and the connection test.⌉⌊
Settings › CompanyStack, with the getting started panel and the connection test.⌉[
Settings › CompanyStack, with the getting started panel and the connection test.
## Blocks
This plugin provides 5 blocks.
* Company Profile Card (UK) Shows a UK company's Companies House profile: status,
number, type, registered office, SIC codes and filing dates.
* Company Search (UK) A company name field that suggests UK companies as you
type. Choosing one fills in matching fields in the surrounding form.
* UK Company Status Badge A badge showing that a company is registered and active
at Companies House, linked to the official record. It does not verify who runs
the website.
* Company Lookup Form (UK) A ready-made form: visitors type a company name, choose
it, and the company number and registered address are filled in. Choose a design,
which fields show and an optional send button.
* UK Business Directory Lists UK companies by SIC code, postcode, town or name,
with an optional visitor search form.
## Installation
1. Install the plugin from Plugins › Add New (search for “CompanyStack”), or upload
the `companystack` folder to `/wp-content/plugins/`, then activate it.
2. Get a free API key at [companystack.co.uk/signup](https://companystack.co.uk/signup).
3. Go to **Settings › CompanyStack**, paste the key, click **Test connection**, then**
Save Changes**.
4. Add a CompanyStack block (Company Lookup Form, Company Search, Company Profile
Card, UK Company Status Badge or UK Business Directory), a pattern or a shortcode
to any page. The “Getting started” panel on the settings screen can make a draft
page for you.
5. Optional: choose a design and colours under **Settings › CompanyStack › Appearance**.
Optionally, put the key in `wp-config.php` instead of the database:
```
define( 'COMPANYSTACK_API_KEY', 'cs_your_key_here' );
```
## FAQ
### Is it free?
The plugin is free and open source (GPL). It needs a CompanyStack API key; the free
plan requires no card and runs every feature, with smaller limits. Paid plans are
for busier sites that need more requests per day or bigger directories.
### Do I need an account?
Yes: a CompanyStack API key, which is free and needs no payment card. Get one at
[companystack.co.uk/signup](https://companystack.co.uk/signup), paste it under Settings›
CompanyStack and click Test connection.
### Is this an official Companies House plugin?
No. CompanyStack is an independent service and is not affiliated with, or endorsed
by, Companies House. The data originates from the public register under the Open
Government Licence v3.0, and each card and badge links to the official record.
### How does the WooCommerce integration work?
With WooCommerce active, the checkout Company field suggests UK companies, and choosing
one fills in address line 1 and 2, town, county and postcode, plus the company registration
number field. The number is validated and saved with the order and shown in the
order screen and emails. With the Checkout block, first make the Company field visible
in the block’s settings. Both options can be switched off under Settings › CompanyStack.
### What is the Company Lookup Form?
A complete form supplied by the plugin, as the Company Lookup Form block or `[companystack_form]`.
It has a company name field with suggestions and the fields it fills in: company
number, two address lines, town, county, postcode and company status. In the block
settings (or with shortcode attributes) you choose which fields show, their labels
and the placeholder.
Switch on “Add a send button” (`show_submit="true"`) and the form emails what the
visitor entered to the site administrator. Nothing is saved in the database and
nothing is sent to CompanyStack beyond the company search itself. Developers can
handle submissions with the `companystack_form_submitted` action, change or reject
them with the `companystack_form_submission` filter, change the email with `companystack_form_email`,
or switch the email off with `companystack_form_send_email`. Without a send button
the fields simply join any form they sit inside.
### Styling: how do I change how it looks?
Three ways, from simplest to most flexible.
1. **Settings › CompanyStack › Appearance.** Choose one of six designs (Clean, Soft,
Underline, Card, Compact inline, Inherit theme), an accent, text and surface colour,
corner radius, field size, font and how dense the suggestions list is, with a live
preview. Leave colours empty to follow your theme.
2. **Per block or shortcode.** Each block has a Design panel (design, corner radius,
accent colour and, for blocks with fields, field size). The form, search and directory
blocks also support the editor’s own colour, typography, spacing and border controls;
the profile card supports colour, typography and spacing. Shortcodes take `preset`,`
size`, `accent`, `text`, `surface` and `radius`, for example `[companystack_form
preset="card" accent="#0a7d5a" radius="12"]`.
3. **CSS custom properties.** Set any of these on `:root` or on a wrapper: `--cstk-
accent`, `--cstk-on-accent`, `--cstk-text`, `--cstk-muted`, `--cstk-surface`, `--
cstk-border`, `--cstk-radius`, `--cstk-font`, `--cstk-control-height`, `--cstk-
shadow`, `--cstk-space`, and for status colours `--cstk-ok`, `--cstk-ok-bg`, `--
cstk-bad`, `--cstk-bad-bg`, `--cstk-warn`, `--cstk-warn-bg`.
Stable class names: every component has the class `cstk` plus its design (`cstk--
clean`, `cstk--soft`, `cstk--underline`, `cstk--card`, `cstk--inline`, `cstk--inherit`)
and size (`cstk--size-compact`, `cstk--size-regular`, `cstk--size-large`). Fields
are `.cstk-input`, labels `.cstk-label`, buttons `.cstk-button`. Components are `.
companystack-form`, `.companystack-search`, `.companystack-card`, `.companystack-
badge`, `.companystack-directory` and the suggestions list `.companystack-ac` (options`.
companystack-ac__option`, name `.companystack-ac__name`, details `.companystack-
ac__meta`).
Filters: `companystack_suggestion_template` (the markup of one suggestion, with
the placeholders `{company_name}`, `{company_number}`, `{status}`, `{postcode}`
and `{sic_description}`), `companystack_autofill_targets` (which fields are filled,
by CSS selector), `companystack_form_fields` (the lookup form’s fields) and `companystack_theme_accent`(
the accent borrowed from your theme).
The suggestions list attached to Contact Form 7, WPForms, Gravity Forms and WooCommerce
fields uses the site-wide design and takes its colours from the field it belongs
to, so it suits dark themes without any set-up. The plugin never restyles those
forms.
### How do I auto-fill a Contact Form 7 form?
Add CSS classes to the form tags:
```
[text company class:companystack-autocomplete]
[text company-number class:companystack-fill-company_number]
[text address class:companystack-fill-address_line_1]
[text town class:companystack-fill-town]
[text postcode class:companystack-fill-postcode]
```
The script loads automatically on pages with such a form.
### How do I auto-fill WPForms or Gravity Forms?
Open the field’s Advanced settings and enter `companystack-autocomplete` in “CSS
Classes” for the company name field, and `companystack-fill-postcode` (etc.) for
the fields to fill. Available fields: `company_number`, `address_line_1`, `address_line_2`,`
town`, `county`, `postcode`, `country`, `address` (the whole address on one line),`
company_status`, `company_type`, `date_of_creation` and `sic_codes`.
### How do I auto-fill my own HTML form?
Mark the fields with data attributes and add `[companystack_autofill]` (or the Company
Search block) to the page:
```
```
Developers can also map fields by CSS selector with the `companystack_autofill_targets`
filter, and listen for the `companystack:select` browser event, whose `detail.company`
holds the chosen company.
### Which shortcodes are there?
* `[companystack_form preset="card" title="Find your company" show_number="true"
show_address1="true" show_address2="true" show_town="true" show_county="false"
show_postcode="true" show_status="false" show_contact="false" show_submit="false"
submit_label="Send"]` (labels: `label`, `placeholder`, `label_number`, `label_address1`,`
label_address2`, `label_town`, `label_county`, `label_postcode`, `label_status`)
* `[companystack_search label="Company name" name="company_name" number_name="company_number"
show_details="true"]`
* `[companystack_card number="00445790" show_address="true" show_sic="true" show_filings
="true"]`
* `[companystack_badge number="00445790" show_name="true" link="true" show_inactive
="false"]`
* `[companystack_directory sic="62012" postcode="M1" town="" query="" status="active"
limit="10" layout="list" show_filter="false"]`
* `[companystack_autofill]`
Every shortcode except the last also takes the design attributes `preset`, `size`,`
accent`, `text`, `surface` and `radius`.
### Is my API key exposed to visitors?
No. The key is only used by your web server. Visitors’ browsers call your site’s
own REST endpoints (`/wp-json/companystack/v1/…`), which are nonce-protected and
rate limited per visitor.
### What data does the plugin store?
Settings (including the API key) in one option, the appearance choices in a second,
a note of which welcome messages you have dismissed in a third, cached API answers
and short-lived rate-limit counters as transients, and, if enabled, the company
registration number on WooCommerce orders. Company Lookup Form submissions are emailed,
not stored. Deleting the plugin removes everything except order data.
### What happens if the service is unavailable or my limit is reached?
Forms keep working as normal text fields, cards, badges and directories are simply
left out for visitors, and administrators see an explanatory notice on the page
and on the settings screen. The plugin pauses requests briefly after errors so it
never slows your site down.
### I use full-page caching. Will search still work?
Search requests carry a WordPress nonce, which is valid for up to 24 hours. If your
cache keeps pages longer than about 12 hours, exclude the pages with company search
forms (for example the checkout) or lower the cache lifetime. Cards, badges and
directories are rendered on the server and cache normally.
### My site is behind a proxy or CDN. Is rate limiting per visitor?
By default the limit uses the connecting IP address, which behind a proxy may be
the proxy’s. If your proxy sets a trusted header, return the real address with the`
companystack_client_ip` filter.
## Reviews
There are no reviews for this plugin.
## Contributors & Developers
“CompanyStack – UK Company Search & Directory” is open source software. The following
people have contributed to this plugin.
Contributors
* [ CompanyStack ](https://profiles.wordpress.org/swilson23/)
[Translate “CompanyStack – UK Company Search & Directory” into your language.](https://translate.wordpress.org/projects/wp-plugins/companystack)
### Interested in development?
[Browse the code](https://plugins.trac.wordpress.org/browser/companystack/), check
out the [SVN repository](https://plugins.svn.wordpress.org/companystack/), or subscribe
to the [development log](https://plugins.trac.wordpress.org/log/companystack/) by
[RSS](https://plugins.trac.wordpress.org/log/companystack/?limit=100&mode=stop_on_copy&format=rss).
## Changelog
#### 1.2.0
* New: a design system for everything the plugin shows, built on CSS custom properties(`--
cstk-*`). It inherits your theme’s font and colours, picks an accent from the
theme palette, and respects dark themes, right-to-left languages, high-contrast
mode, zoom and reduced motion.
* New: six designs to choose from: Clean, Soft, Underline, Card, Compact inline
and Inherit theme.
* New: Company Lookup Form block and `[companystack_form]` shortcode, with a choice
of fields, labels and an optional send button that emails the site administrator(
nothing is stored; developers get an action and filters).
* New: Settings › CompanyStack › Appearance, with a live preview, WCAG contrast
warnings and a reset button.
* New: design controls on every block (design, corner radius, accent colour, field
size) and support for the editor’s colour, typography, spacing and border settings
where they apply; matching shortcode attributes.
* New: four block patterns, a getting started panel that makes draft pages from
them, and a “Test connection” result that says what your key’s plan allows.
* New: the suggestions list shows each company’s status as a pill, takes its colours
from the field it belongs to, and can be made more compact. Home and End move
to the first and last suggestion.
* New: filters `companystack_suggestion_template`, `companystack_form_fields`, `
companystack_form_submission`, `companystack_form_email`, `companystack_form_send_email`
and `companystack_theme_accent`; action `companystack_form_submitted`.
* Fixed: a letters-only postcode area such as NE or M is now accepted in the directory(
it used to be dropped, so the directory ignored the filter), and a postcode that
cannot be read now shows a message.
* Fixed: the suggestions list says “Searching UK companies…” while a search runs.
* Fixed: the directory search form is aligned and styled, grid entries no longer
overlap, entries no longer break in the middle of a company number or date, the
badge title is bold with a larger icon, the profile card gives its values more
room, and the “Test connection” result sits beside its button.
* Changed: the stylesheet is loaded by the blocks and shortcodes themselves, so
it appears only on pages that use them.
* Changed: the one admin notice (on the Plugins screen, until a key is saved) can
now be dismissed.
* Readme: states plainly that CompanyStack is independent of Companies House.
#### 1.1.2
* Clearer description: company data comes from the Companies House register as
held and updated by CompanyStack, not from live Companies House calls.
* Tested with WordPress 7.1.
#### 1.1.1
* The badge now reads “Active UK company” and, on hover, says it shows the register
entry only and does not verify who runs the website. The block is renamed UK
Company Status Badge; existing blocks and shortcodes keep working.
* The source line under cards and directories says the data comes from Companies
House via CompanyStack, which accepts no responsibility to anyone who relies
on it, and to check important information against the official record. This keeps
sites that show CompanyStack data in line with its Terms (clause 15B).
#### 1.1.0
* Rebuilt on the CompanyStack API at api.companystack.co.uk; the old API address
no longer works, so please update.
* Security: the API key is no longer sent to browsers. All look-ups go through
nonce-protected, rate-limited REST endpoints on your own site.
* New: blocks for Company Search, Company Profile Card, Verified UK Company Badge
and UK Business Directory.
* New: WooCommerce checkout company autocomplete and company registration number
field (Checkout block and classic checkout, HPOS compatible).
* New: auto-fill for Contact Form 7, WPForms, Gravity Forms and any HTML form via
CSS classes or data attributes.
* New: business directory by SIC code, postcode area, town or name, with optional
visitor search and pagination on paid plans.
* New: settings screen with connection test, plan limits, cache controls and a
privacy-policy suggestion.
* Removed jQuery dependency, activation redirect and unused CRM code.
* Uninstall now removes all settings and cached data.
#### 1.0.0
* Initial release.
## Meta
* Version **1.2.0**
* Last updated **1 day ago**
* Active installations **Fewer than 10**
* WordPress version ** 6.3 or higher **
* Tested up to **7.1.3**
* PHP version ** 7.4 or higher **
* Tags
* [autocomplete](https://wordpress.org/plugins/tags/autocomplete/)[business directory](https://wordpress.org/plugins/tags/business-directory/)
[companies house](https://wordpress.org/plugins/tags/companies-house/)[woocommerce](https://wordpress.org/plugins/tags/woocommerce/)
* [Advanced View](https://wordpress.org/plugins/companystack/advanced/)
## Ratings
No reviews have been submitted yet.
[Your review](https://wordpress.org/support/plugin/companystack/reviews/#new-post)
[See all reviews](https://wordpress.org/support/plugin/companystack/reviews/)
## Contributors
* [ CompanyStack ](https://profiles.wordpress.org/swilson23/)
## Support
Got something to say? Need help?
[View support forum](https://wordpress.org/support/plugin/companystack/)