PQQ vs ITT vs SQ: What UK Bid Writers Need to Know

If you are new to public sector bidding in the UK, the alphabet soup of procurement documents is genuinely confusing. PQQ, ITT, SQ, RFP, EOI — each represents a different stage or type of competitive process, and conflating them costs time and sometimes disqualifies bids.

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The Core Documents You Will Encounter

Pre-Qualification Questionnaire (PQQ)

A PQQ is used to shortlist suppliers before the full tender stage. It screens out organisations that lack the financial standing, technical capability, or relevant experience to compete.

Typical PQQ content:

• Company financials (turnover, accounts)
• Insurance certificates
• Relevant contract references (usually 3, within the past 3–5 years)
• Health & safety policy
• Equality and diversity policy
• GDPR compliance statement

Key point: PQQs are largely pass/fail. You need to meet minimum thresholds. Gold-plating your answer to a PQQ question that has a binary "yes/no" pass threshold wastes effort. Focus on clarity, not length.

The PQQ process has been reduced in central government procurement since the Crown Commercial Service moved many frameworks to open competition — but it remains widespread in NHS, local authority, and housing association procurement.

Selection Questionnaire (SQ)

The SQ replaced the PQQ in above-threshold public contracts in England and Wales from 2016 (Cabinet Office standardisation). It serves the same shortlisting purpose but with a standardised format across most central government and local authority procurement.

In practice: If you hear "SQ," treat it like a PQQ. The questions are structurally similar. The main advantage of the SQ is that responses can often be reused across multiple opportunities with minor adaptation.

Bid Refinery treats SQ and PQQ stages equivalently in its requirements extraction — both are analysed for gate criteria and mandatory fields.

Invitation to Tender (ITT)

An ITT is the main competitive stage after shortlisting. It is where the substantive evaluation happens and where bid quality has the most impact on the outcome.

ITT documents typically include:

• Specification of requirements (detailed)
• Evaluation criteria and weightings
• Pricing schedule
• Draft contract terms
• Instructions to tenderers (format, submission method, deadlines)
• Questions for written response (Method Statements)

ITT responses are where bid writing skill matters most. Unlike PQQs, ITT questions are often qualitative, scored on a scale (e.g., 0–5 or 0–10), and explicitly weighted. A question worth 30% of the technical score deserves proportional investment.

The ITT is almost always submitted electronically via a procurement portal (Jaggaer, Proactis, Delta, Atamis, or the buyer's own system). Formatting requirements are strict — violations lead to disqualification.

Request for Proposal (RFP)

RFP is used more commonly in private sector procurement and for complex, consultancy-style engagements in the public sector. Unlike an ITT (which specifies what is needed), an RFP invites suppliers to propose a solution.

The distinction matters: ITT responses follow the buyer's structure. RFP responses require you to articulate your own methodology, which gives more freedom and demands more strategic thought.

Expression of Interest (EOI)

An EOI is a low-commitment, early-stage document used to gauge market interest before a buyer formally procures. Responding to an EOI does not commit you to the full tender.

EOIs are useful intelligence-gathering opportunities. They tell you the buyer's intent, likely timeline, and sometimes reveal whether the requirement already has a preferred supplier (watch for suspiciously specific technical requirements).

Dynamic Purchasing System (DPS)

A DPS is an electronic system established by a contracting authority where any eligible supplier can apply to join throughout its life. Once admitted, suppliers can bid on individual call-off contracts.

DPS applications are similar to SQs in content. The difference is ongoing: new suppliers can join at any time, unlike a framework that is closed once established.

Procurement Routes at a Glance

Document	Stage	Purpose	Evaluation
EOI	Pre-market	Gauge interest	No formal scoring
PQQ / SQ	Shortlisting	Filter eligible suppliers	Pass/fail + minimum thresholds
ITT	Full tender	Select winning bid	Scored (quality + price)
RFP	Full tender	Invite proposed solutions	Scored (quality + price)
DPS Application	Ongoing	Join approved list	Pass/fail

Which One Are You Responding To?

The document you have been issued determines your strategy:

• PQQ/SQ: Focus on compliance and brevity. Meet every minimum threshold. Do not pad.
• ITT: Invest in quality per weighted question. Treat each method statement as a scored piece of work.
• RFP: Lead with your methodology. The buyer wants to see thinking, not just credentials.
• DPS: Complete accurately and keep a record for re-use.

Getting this wrong is more common than it sounds. Teams that apply ITT-level effort to PQQ questions burn hours unnecessarily. Teams that apply PQQ-level brevity to scored ITT method statements lose marks.

Bid Refinery's analysis automatically classifies the document type from the tender pack and structures your response plan accordingly — so you know what you are dealing with before the writing starts.