SIC codes let you filter 5 million UK companies by exact industry. Learn how the classification works, where generic "industry" filters fall short, and how to build precise target lists.
Most prospecting tools let you filter by "industry." You pick "Software" or "Marketing" from a dropdown and get a sprawling, noisy list. For the UK market there is a far sharper instrument sitting in public data: the SIC code.
Every UK company is legally required to declare what it does using a Standard Industrial Classification code when it files with Companies House. That single field turns a vague industry guess into a precise, verifiable filter.
A SIC code is a five-digit number describing a company's primary economic activity. The UK uses the 2007 SIC condensed list — just over 700 codes covering everything from sheep farming (01450) to software development.
The precision is the point. "IT" as a generic industry might return tens of thousands of companies. SIC codes split that into:
A managed-service provider, a bespoke software house, and a data-hosting firm are three different buyers with three different pains. SIC codes let you treat them as three different lists.
The big sales databases were built for the US market. Their industry taxonomies are estimated, inconsistently applied, and thin on small UK businesses. A two-person Bristol agency often simply isn't in them — or is tagged with a category someone guessed from a LinkedIn page.
SIC codes are different in two ways that matter:
Stack them with geography. SIC code plus postcode area gives you "software consultancies in Manchester" without the noise. Companies House registered addresses confirm the company operates in the UK and let you target by region.
Watch for multiple codes. A company can list up to four SIC codes. A firm that lists both "management consultancy" and "software development" is often a hybrid — useful context for how you pitch.
Map codes to your ICP, not the other way round. Don't start from the dropdown. Start from your three best customers, look up their actual SIC codes on their Companies House record, and build your target list from those exact codes. Your best-fit segment is usually narrower than any pre-set category.
Combine with company age. SIC code tells you what they do; incorporation date tells you how mature they are. "Software consultancies founded in the last 18 months" is a completely different motion from "software consultancies running for a decade."
SIC codes get you a clean, industry-precise list of legal entities. What they don't give you is contact detail: no email, no direct line, often no website on the record itself.
That's the enrichment step. Once you have the company name and the right industry filter, you resolve the website, find the decision-maker, and verify a contact. The SIC code did the targeting; enrichment makes the list actionable.
KithFlow exposes Companies House SIC and postcode filtering directly, then layers enrichment and sourced dossiers on top — so you go from "all active 62012 companies in Leeds" to a contactable, briefed list without leaving one tool.
If you sell B2B in the UK, the industry dropdown in your US-built tool is costing you precision. SIC codes are free, filed, and far sharper. Start from your best customers' actual codes, stack them with location and company age, and you'll build target lists your competitors can't replicate.