Quick Comparison: SOQ vs SF330 vs RFP vs RFI vs RFQ
Before the detailed explanations, here's the summary. These are the five documents you'll encounter most in AEC procurement.
| Document | Full Name | Who Creates It | What It Covers | Typical Length |
|---|---|---|---|---|
| RFI | Request for Information | Owner / Agency | General interest and capabilities | 2-5 pages |
| RFQ | Request for Qualifications | Owner / Agency | Firm qualifications and experience | Varies by agency |
| SOQ | Statement of Qualifications | The firm | Firm's qualifications, resumes, projects | 10-50 pages |
| SF330 | Standard Form 330 | The firm | A/E qualifications in standardized form | 30-80 pages (Part I) |
| RFP | Request for Proposal | Owner / Agency | Technical approach, team, and price | 20-100+ pages |
The key distinction: RFIs, RFQs, and RFPs are issued by the client or agency. SOQs and SF330s are prepared by the firm in response.
What Is an SOQ (Statement of Qualifications)?
A Statement of Qualifications (SOQ) is a document prepared by a firm to demonstrate its qualifications for a project or contract. Unlike the SF330, an SOQ has no standardized format — the firm controls the layout, content, and emphasis. SOQs typically include a firm overview, staff resumes, project experience sheets, references, and relevant certifications. They are the most common qualification document in state, local, and private-sector AEC procurement.
SOQs are sometimes submitted in response to an RFQ, sometimes proactively as part of a prequalification process, and sometimes as the first phase of a two-step selection where shortlisted firms later submit full proposals.
What Is an SF330?
The SF330 (Standard Form 330) is a federally standardized document used by architecture and engineering firms to demonstrate qualifications for government contracts. It has two parts: Part I is contract-specific and submitted with each proposal, and Part II is a general firm profile updated annually. The SF330 is required for federal A/E procurements under the Brooks Act and widely used by state and local agencies as well.
For a detailed section-by-section guide, see SF330 Guide: What It Is, How to Fill It Out, and Common Mistakes.
What Is an RFP (Request for Proposal)?
A Request for Proposal (RFP) is a solicitation document issued by a client or agency asking firms to submit a detailed proposal for a specific project. An RFP response typically includes the firm's qualifications, proposed team, technical approach or methodology, project schedule, and pricing. RFPs are used when the agency wants to evaluate both qualifications and approach — not just who the firm is, but how they'd execute the work.
In AEC, RFPs often come after a shortlisting phase. The agency narrows the field using qualifications (via SOQ or SF330), then issues the RFP only to shortlisted firms.
What Is an RFQ (Request for Qualifications)?
A Request for Qualifications (RFQ) is a solicitation issued by a client or agency to evaluate firms based on their qualifications, experience, and team — without requesting a technical approach or pricing. Firms respond to an RFQ by submitting an SOQ, an SF330, or whatever format the solicitation specifies. The purpose is to create a shortlist of qualified firms.
One important note: outside of AEC, "RFQ" often means "Request for Quote" (a pricing request). In architecture, engineering, and construction, it almost always means "Request for Qualifications." This causes confusion when people cross industries or search online.
What Is an RFI (Request for Information)?
A Request for Information (RFI) is a preliminary document issued by an agency to gather general information about firms' capabilities and interest in a potential project. RFIs are non-binding — responding to one does not commit you to pursuing the project, and not responding does not disqualify you from future opportunities. RFI responses are typically short (2-5 pages) and focused on firm capabilities and relevant experience.
Agencies use RFIs to gauge market interest, understand what expertise is available, and sometimes to shape the scope of a future solicitation.
How They Relate: The Typical Procurement Sequence
These documents don't exist in isolation. They follow a logical sequence in most AEC procurements.
- Agency issues an RFI (optional) — "We're thinking about this project. Who's interested and what can you do?" Firms respond with brief capability statements.
- Agency issues an RFQ — "We're moving forward. Show us your qualifications." Firms respond with an SOQ or SF330.
- Agency creates a shortlist — Based on qualifications, the agency narrows the field to 3-5 firms.
- Agency issues an RFP to shortlisted firms — "Here's the detailed scope. Tell us how you'd do the work and what it would cost."
- Firms submit full proposals — Technical approach, project team, schedule, pricing.
- Agency selects the winning firm — Often followed by interviews with the top 2-3 firms.
Not every procurement follows all six steps. Some skip the RFI. Some combine the RFQ and RFP into a single solicitation. Federal A/E procurements under the Brooks Act typically stop at step 3 — qualifications-based selection (QBS) means the most qualified firm negotiates the contract directly, without a price competition.
When to Use Each
| Scenario | What You'll Likely Submit |
|---|---|
| Federal A/E contract | SF330 (Part I + Part II) |
| State DOT consultant selection | SF330 or SOQ, depending on the state |
| Municipal infrastructure project | SOQ or modified SF330 |
| Private client requesting qualifications | SOQ in your own format |
| Agency asking who's interested before a solicitation | RFI response (brief capabilities statement) |
| Full project pursuit after being shortlisted | RFP response (qualifications + approach + price) |
What Goes Into Each Document
SOQ typically includes:
- Cover letter addressing the specific opportunity
- Firm overview and capabilities narrative
- Staff resumes for key personnel (tailored to the pursuit)
- Project experience sheets for relevant completed work
- References with current contact information
- Certifications and registrations (DBE, SBE, MBE, WBE, etc.)
- Organizational chart for the proposed team
Staff resumes and project sheets are the core of every SOQ — and the most labor-intensive to prepare. Each client or agency may want a different format, different page limits, and different emphasis. The same engineer's resume gets reformatted dozens of times per year across different pursuits.
SF330 includes:
Nine structured sections (A through I) covering contract information, point of contact, proposed team, org chart, key personnel resumes, project experience, personnel-project matrix, additional information, and authorization. See the full SF330 section-by-section guide for details.
RFP response typically includes:
Everything in an SOQ, plus:
- Technical approach or methodology
- Project understanding and scope interpretation
- Management plan and quality assurance approach
- Project schedule
- Pricing or fee proposal
- Compliance documentation and required forms
Common Confusion Points
"RFQ" means different things in different industries. In AEC, it's almost always "Request for Qualifications." In manufacturing, IT, or general procurement, it usually means "Request for Quote" (pricing). If you're searching online, you'll find a lot of content about RFQs that's about pricing — not qualifications. Make sure the advice you're reading applies to your situation.
SOQs and SF330s both demonstrate qualifications, but they're different formats. An SOQ is freeform — you design the layout and choose what to emphasize. An SF330 is a fixed federal form with specific sections. Some agencies accept either. Some require one or the other. Always check the solicitation.
An RFI is not a commitment. Responding to an RFI doesn't obligate you to bid. Not responding doesn't disqualify you. It's information-gathering, not selection. That said, responding to RFIs builds your relationship with the agency and signals interest.
Not all procurements include every step. A small municipal project might go straight from RFQ to contract negotiation. A large federal program might have an RFI, then an RFQ, then an RFP, then interviews. Read the solicitation carefully to understand which phase you're in.
Frequently Asked Questions
Is an SOQ the same as an SF330?
No. Both demonstrate firm qualifications, but they differ in format. An SOQ is a freeform document where the firm controls the layout and content. An SF330 is a standardized federal form with nine specific sections (Part I) and a general firm profile (Part II). Some agencies accept either, but many specify which format they want. Always follow the solicitation's instructions.
Do I need to respond to every RFQ I receive?
No. Responding to every RFQ dilutes your team's effort and leads to weaker submittals. Use a go/no-go framework to evaluate each opportunity against your firm's strengths, capacity, and strategic goals. It's better to submit five strong SOQs than fifteen mediocre ones.
What's the difference between an RFQ and an RFP in construction?
An RFQ asks for qualifications only — who you are, what you've done, and who would work on the project. An RFP asks for a full proposal including technical approach, schedule, and often pricing. The RFQ typically comes first to create a shortlist, and the RFP goes to shortlisted firms only. Some solicitations combine both into a single document.
Can an SOQ be used for multiple pursuits?
The firm overview and general capabilities sections can be reused. But staff resumes, project sheets, and the cover letter should be tailored to each pursuit. Evaluators can tell when a firm submits a generic package that wasn't customized for their specific project. The tailoring is what separates shortlisted firms from the rest.
How long should an SOQ be?
Follow the solicitation's page limits. If no limit is specified, 15-30 pages is typical for most state and local procurements. Shorter is better — evaluators review many submittals and value conciseness. Every page should directly support the evaluation criteria. If a section doesn't help your score, cut it.