AIA Contracts Explained Simply: Which One Do You Need?

What Are AIA Contracts? (The Simple Version)

AIA stands for the American Institute of Architects. They created standard contract templates that are used all over the country for construction projects. Think of them like fill-in-the-blank forms that spell out the deal between you (the contractor) and the building owner.

There are over 200 AIA forms, but don't panic — for most jobs in NYC, you only need to know about 4 documents. This guide will tell you which one fits your situation.

The big question most contractors have: 'The owner asked me to send THE AIA contract — but which one?' The answer depends on how the job is priced.

The 4 Documents You Need to Know

Here's the simple breakdown. There are really only two pricing scenarios in construction, and each one has its own AIA contract:

• Fixed price job, big project (you quoted one number for the whole job) → Use AIA A101
• Fixed price job, small project (under $250K, simpler paperwork) → Use AIA A104
• Cost-plus job (the owner pays your costs + your fee) → Use AIA A102 for big jobs, or A103 for smaller jobs
• All of these come with a companion document called A201 — the 'rules of the game' that both sides agree to follow

That's it. Those are the five. Let's look at each one.

A101 — For Fixed Price Jobs

This is the most common one. If you gave the owner a price — say $150,000 to do the work — and they accepted it, A101 is your contract.

When to use it: You know exactly what the work is. There are drawings and specs. You gave a number and the owner said yes. Simple.

What it covers: How much you get paid, when you get paid, what happens if the work changes, and what to do if there's a disagreement.

A104 — For Fixed Price Jobs (Small Projects)

A104 is the shorter, simpler version of A101. Same idea — fixed price — but designed for smaller projects where you don't need a complicated contract. Think of it as A101's little brother.

When to use it: The job is under $250,000. The scope is clear and simple. You want a fixed price contract but without all the extra paperwork of A101. Great for apartment renovations, small building repairs, and straightforward commercial work.

The big difference from A101: A104 is much shorter and easier to read. It doesn't require A201 (the 40-page rulebook) — the general conditions are built right into the document. This makes it faster to set up and easier for both sides to understand.

A102 — For Cost-Plus Jobs (Big Projects)

Sometimes the owner doesn't want a fixed price — maybe the job is too complicated or there are too many unknowns (like renovation work where you don't know what's behind the walls). In this case, the owner pays your actual costs plus a fee for your work.

When to use it: The scope isn't fully clear. It's a renovation with surprises expected. The owner prefers to see exactly where the money goes. The project is over $250,000.

Important: A102 can include something called a GMP (Guaranteed Maximum Price) — basically a cap. The owner says 'I'll pay your costs plus fee, but the total can't go over $X.' This protects the owner while still giving you flexibility.

A103 — For Cost-Plus Jobs (Small Projects)

A103 is the simpler version of A102. Same idea — the owner pays your costs plus a fee — but with less paperwork. It's designed for smaller, more straightforward jobs.

When to use it: The job is under $250,000. It's a residential renovation, small commercial fit-out, or repair project. You don't need a 50-page contract for a bathroom renovation.

This is probably the right choice for a lot of the work contractors do in NYC — apartment renovations, building repairs, small commercial jobs.

A201 — The Rulebook (Always Included)

A201 isn't a contract by itself — it's like an instruction manual that comes with A101 or A102. It explains the rules both sides follow during the project.

What's in it: How payments work step by step. What happens when the owner wants to change the work. Insurance you need to have. What to do if there's a problem or disagreement. When the architect can and can't tell you what to do.

Why it matters: A lot of contractors skip reading A201 because it's long (40+ pages). This is a mistake. Many of the rules that affect your money — like when you get paid, how much the owner can hold back, and what happens with changes — are all in A201, not in the main contract.

5 Things to Watch Before You Sign

AIA contracts are fair overall, but there are specific things you should check and possibly negotiate before signing:

• Retainage (money held back): The standard is 10% — meaning the owner holds back 10% of every payment until the job is done. Try to negotiate it down to 5%, or ask for it to drop to 5% after you're halfway done. That money sitting in the owner's pocket is YOUR money.
• When you get paid: The contract says the owner has 30 days to pay after you submit your invoice. Make sure this is actually followed. If they're slow, add a clause that says they owe you interest on late payments.
• Change orders (extra work): NEVER do extra work based on a verbal 'go ahead.' Always get it in writing before you start. If there's a dispute later, a verbal agreement is almost impossible to prove.
• The scope of work: The contract price only means something if what's included is clearly written down. Attach your proposal, drawings, and a clear list of what's NOT included. This protects you from 'I thought that was part of the price.'
• Don't start work without a signed contract: This sounds obvious, but it happens all the time. If a problem comes up and there's no signed contract, you have very little legal protection.

Common Mistakes to Avoid

These are the mistakes we see contractors make most often — and they're all avoidable:

• Using A101 (fixed price) when the scope isn't clear — this leads to fights about extras and change orders
• Not reading A201 — you signed a 40-page document you never read, and now there's a rule you didn't know about
• Not customizing the contract — AIA contracts are templates meant to be adjusted for each job. Use them as-is and you might be leaving money on the table
• No clear scope of work attached — the contract says $150,000 but doesn't clearly say what's included, so the owner expects things you didn't plan for
• Starting work before the contract is signed — 'We'll get the paperwork done later' is the most expensive sentence in construction

Need Help? We're Here

If you're not sure which contract to use, or you need someone to review the clauses before you sign — that's completely normal. Construction contracts can be confusing even for experienced contractors.

At ARCONDES, we help contractors with contract questions as part of our consulting services. Whether you need help picking the right form or understanding specific clauses, we'll walk you through it in plain language. Call us or send a message — there's no charge for the initial conversation.