How to Get onto a Tier 1 Contractor's Supply Chain

For a groundworks, drainage, piling or utilities firm, a place on a tier 1 contractor's supply chain can change the shape of the business. The work is larger, more regular and often tied to long programmes. It also comes with more paperwork than most owner-led firms are used to, and a supply chain manager who has dozens of firms asking for the same thing you are.

This guide is for SME civils and specialist subcontractors who want to get onto those lists and stay there. It covers what tier 1 contractors look for, how registration portals and pre-qualification work, how public sector frameworks work under the Procurement Act 2023, how to get noticed by the people who make the decisions, and what keeps you on the list once you are there.

What a tier 1 contractor is, and where you fit

A tier 1 contractor holds the main contract with the client: a public body, a utility, a developer or a private owner. Tier 2 firms are the specialist subcontractors and suppliers who hold contracts with the tier 1, and tier 3 firms work for them in turn. The government's Construction Playbook describes early supply chain involvement as formally engaging the tier 1 contractor alongside tier 2 and 3 sub-contractors and suppliers in the preconstruction phase,¹ so on well-run public schemes the better subcontractors are now brought in before the design is fixed.

Most UK tier 1s keep an approved or preferred supplier list for each trade and region. Getting onto that list is the first step. Being invited to price regularly, and winning, is the second. The two are not the same, and plenty of firms are approved on paper but never asked to tender.

What tier 1 contractors look for in a subcontractor

Supply chain teams are managing risk. A failed subcontractor costs them programme, money and sometimes their own framework place, so they check the same things every time. Have the evidence for each one ready before you make contact.

Financial standing

Expect your accounts to be scrutinised. The Construction Playbook says that to safeguard the delivery of public sector projects, it is critical that suppliers' economic and financial standing is considered during selection.¹ Tier 1s apply the same thinking down their own chain. A small firm with thin reserves can still be approved, but usually for smaller packages to start with.

Accreditations: SSIP and the Common Assessment Standard

Two schemes do most of the work here. Safety Schemes in Procurement (SSIP) is an umbrella for health and safety assessment schemes, and its member schemes agree to accept a current, valid approval from any other member, as long as the details are displayed on the SSIP Portal.² That means one SSIP certificate should satisfy any buyer who accepts SSIP.

The Common Assessment Standard, developed by Build UK, goes further and covers full pre-qualification. Certified companies are assessed once a year by a Recognised Assessment Body, at either desktop or site-based level, and Build UK says central government departments and wider public sector bodies should use it to pre-qualify suppliers.³ Our guide to Constructionline, CHAS and PAS 91 covers which scheme to choose and how the levels compare.

Social value and carbon reporting

These questions flow down from the client. Under PPN 002, central government departments must apply a minimum 10% weighting of the total score to social value,⁴ and tier 1s bidding for that work ask their supply chain to help them score it. Under PPN 006, central government buyers should take account of bidders' Carbon Reduction Plans, which set out their commitment to net zero, on contracts worth more than £5 million a year.⁵ A subcontractor is not usually required to publish one, but a short, honest record of local hires, apprentices and fuel or plant emissions puts you ahead of firms that have nothing.

How supply chain registration and pre-qualification work

Most tier 1s run supplier registration through an online portal or a third-party platform. The details differ, but the route is broadly the same.

Registration is usually free. The cost is in the accreditation behind it and the time to fill it in properly. Answer the trade and region questions narrowly. If you tick every category, you are filed with the general contractors and rarely matched to the packages you are best at. Keep insurance and accreditation dates current, because an expired certificate can drop you off a list without anyone telling you.

How public sector frameworks work

Much tier 1 work in civils comes through public sector frameworks, so it helps to know how they run. The Procurement Act 2023 came into force on 24 February 2025, and procurements started under the old rules continue under the old legislation.⁶

The Act defines a framework as a contract between a contracting authority and one or more suppliers that provides for the future award of contracts.⁷ The individual jobs awarded under it are call-off contracts. In most cases a framework does not commit the authority to award any call-off at all,⁷ which is why a framework place is a licence to compete rather than guaranteed work.

• Term: most frameworks can last up to four years, and utilities and defence frameworks up to eight.⁷
• Open frameworks: a new type under the Act that must be reopened at least once in its first three years and at least every five years after, lasting eight years in total, and new suppliers can be added when it reopens.⁷
• Lots: authorities must consider splitting work into lots, which the guidance notes can make it easier for SMEs to bid for smaller contracts or smaller parts of larger ones.⁸
• Transparency: authorities must now publish a contract award notice after each call-off,⁷ so you can see which contractors are winning work.

Where opportunities are published

Find a Tender is the central digital platform under the Procurement Act. It is free to use for everyone, and you only need to register when you want to bid. Registration asks for your Companies House number, address, the last two years of accounts and details of connected people and any convictions.⁹ Contracts Finder lets you search for contracts worth over £12,000 including VAT with the government and its agencies.¹⁰ Scotland, Wales and Northern Ireland have their own portals.

The procurement threshold for works contracts is £5,193,000 including VAT from 1 January 2026 to 31 December 2027.¹¹ Large civils frameworks are usually let in packages well above that, which is one reason SMEs most often reach them through a tier 1.

Use the notices to find your tier 1

The most useful habit for a subcontractor is reading the notices, not just the tenders. Contracting authorities spending more than £100 million a year must publish a pipeline notice for each opportunity over £2 million expected in the next 18 months.¹² Together with call-off award notices, that tells you which schemes are coming, in which region, and which tier 1s are winning. Those are the supply chain teams to contact, months before they need to fill a package.

If you want to bid for a framework in your own right, start with the lots aimed at smaller packages or a single region, and build a record of delivery first. Most SMEs find that working under a tier 1 on the same framework is the faster route to the evidence a direct bid needs.

How to get noticed by supply chain managers

Approval gets you onto the list. Being remembered gets you invited to price. Supply chain managers are busy, and they shortlist the firms they know and can check quickly.

Meet-the-buyer events

Tier 1s, clients and local authorities run supplier days and meet-the-buyer events, often at the start of a new framework or a large scheme. Go with a one-page capability sheet, two or three relevant projects and a clear answer to which packages you want. Follow up within a week with the same information by email, and register on their portal the same day if you have not already.

Case studies on your website

Almost every supply chain manager will look at your website before they call. Write your projects out in full: the client type, scope, value band, constraints such as live traffic or possessions, how you dealt with them, and the outcome. A page per service and region, with those projects linked, answers their questions before they ask. Our website builds start from exactly this structure, and search work makes sure buyers looking for a specialist in your area can find it.

LinkedIn, through people

Supply chain, commercial and project managers at tier 1s are on LinkedIn, and they follow people rather than company pages. Short, specific posts from your directors and engineers about schemes completed, problems solved and new accreditations keep your name in front of them. Once that is in place, targeted LinkedIn campaigns can put your case studies in front of supply chain staff at the specific contractors winning work in your region. We cover the wider approach in digital marketing for engineering companies and civils firms.

How to keep your place: performance and payment

Staying on a supply chain is mostly about delivery, and about making delivery easy to see. Tier 1s score their subcontractors on safety, quality, programme and commercial behaviour, often quarterly, and those scores decide who is invited to price next.

• Report without being chased. Daily diaries, progress photos, quality records and accident reporting in the format the tier 1 asks for, on time.
• Raise problems early. Early warnings and variations notified in writing, with the date, location and quantities, are easier to agree than claims assembled months later.
• Keep paperwork current. Insurance, accreditation and training records that lapse can suspend you automatically.
• Ask for your scores. If the tier 1 rates its supply chain, ask to see yours and what would move it.

Clean reporting is easier when site and office run on the same system. Eccles, a Walsall manufacturer supplying utility and infrastructure clients, replaced fragmented systems with a custom ERP that brought CRM, stock, vendor data and operations together, and real-time visibility across operations replaced manual reporting. Read the Eccles case study.

Know your payment rights

On public work, the Procurement Act implies 30-day payment terms into most public contracts and passes them down by implying the same terms into most public sub-contracts.¹³ If you are working under a tier 1 on a public scheme, that applies to your invoices too, with some exceptions such as concession and private utility contracts.

Check a tier 1's record before you sign. Large businesses must publish their payment performance at least twice a year, and you can search for the average time a company takes to pay and the proportion of payments it makes late.¹⁴ Across the construction sector, large businesses took a median 33 days to pay in 2025, and 14% of their invoices by number were paid late.¹⁵ In March 2026 the government also proposed banning the withholding of retention payments in construction contracts, subject to consultation.¹⁶

A 90-day plan to get on a tier 1 supply chain

If you are starting from scratch, this is the order we would work in. Tick items off as you go; the list saves in your browser.

None of this is quick, and the first package from a new tier 1 is usually small. Deliver it well, report it cleanly and write it up as a case study, and the next invitation tends to follow. If you want to see where your own marketing stands before you start approaching supply chain teams, the marketing score calculator gives a quick benchmark.