Types of business contracts, and which ones need a signed writing

Most types of business contracts you'll sign this year won't look like contracts. A purchase order, a clicked checkbox, an emailed "approved, go ahead" can bind you as tightly as a forty-page agreement from outside counsel. Format isn't what decides it.

Restatement (Second) of Contracts § 17 puts formation simply: you need a bargain, meaning mutual assent to an exchange, plus consideration. Section 71 defines consideration narrowly. The performance or return promise has to be bargained for, sought by the promisor in exchange for the promise and given by the promisee in exchange. A gift promise fails that test.

Two more elements come from general doctrine: capacity, and a lawful purpose. Miss either and there's nothing to enforce.

Sales of goods are looser. UCC § 2-204 says a sale-of-goods contract can be formed "in any manner sufficient to show agreement," including by conduct, and it doesn't fail for indefiniteness where the parties meant to contract. That's why a shipped-and-paid purchase order binds both sides. If the wording bothers you, contract vs. agreement covers that distinction.

Lawyers don't sort contracts by industry. They sort them by which legal consequence follows, and the seven rows above are the distinctions every list of types of legal contracts online is built from.

Two of them surprise people. A quasi-contract, or implied-in-law contract, binds someone who never intended to be bound, so a court can stop unjust enrichment. And adhesion contracts, which Cornell's Wex defines as agreements between parties of such disproportionate bargaining power that the weaker side could not have negotiated the terms, are most of what you accept in a week.

What the table leaves out is form. Whether a contract has to be written down is a separate question from what kind of contract it is.

Doctrine tells you how a contract behaves. This list tells you what's in the folder. These are the types of business contracts a US company of five to two hundred people signs most often.

Sales and purchase agreements

Goods change hands for money, which puts the deal under UCC Article 2 rather than common law. That changes three things at once. Formation is loose: under § 2-204 conduct alone can make the contract, and it doesn't fail for indefiniteness. The gap-fillers are the Code's rather than your draft's, so terms you never negotiated still bind you. And past $500 the writing rule in § 2-201 applies, which is the single most-missed line in small-business contracting. Article 2 doesn't reach services, so a deal mixing equipment and installation goes to whichever part predominates, and courts split on where that line falls.

Purchase orders and supply agreements

These work as a pair. A PO is an offer, and acceptance often happens by shipping rather than by anyone signing. The supply agreement sitting above it fixes price, volume and lead time for the year, so the PO only has to carry quantity and date.

Master service agreements

One MSA holds the legal terms, liability, IP ownership and termination, while each statement of work adds scope, timeline and price. It is the cheapest structure if you sell the same service repeatedly, because liability and IP get negotiated once instead of every quarter. It is also the most common overreach: an MSA for a single three-month engagement buys three weeks of legal review nobody needed. The test is whether you expect a second SOW. If the answer is no, a standalone services agreement does the same job in a fifth of the pages.

Service and consulting agreements

One-off work where an MSA is overkill. Article 2 doesn't apply, so common law fills the gaps, which in practice means your draft carries more weight because there is no Code standing behind it.

Independent contractor agreements

This one does double duty. It sets the commercial terms, and it documents the facts supporting the classification. Titling a document "contractor agreement" proves nothing on its own; what the parties actually do is what gets weighed.

Non-disclosure agreements

One-way or mutual, and that difference matters more than most people check before signing. A one-way NDA presented as standard is a negotiating position, not a formality. The clauses that decide enforceability are the definition of confidential information, the carve-outs for what was already public or independently developed, the term, and what happens to the material at the end. Our NDA template guide goes through them in order. Confidentiality and non-competition are separate promises, and conflating them is how companies end up relying on a clause their state will not enforce.

Employment agreements and offer letters

An offer letter confirms pay, start date and at-will status, and deliberately promises no term. The employment agreement is fuller, usually with a fixed term and restrictive covenants, and it converts an at-will relationship into a negotiated one.

Commercial leases

An interest in land, so a signed writing is required no matter how friendly the landlord is. Long leases get recorded, and recording brings a notary into it in many states.

Equipment leases

The same shape with a different asset, usually with a purchase option at the end of the term. The option is where the real money sits, and it is the clause most often left at the drafter's default.

Software and IP licenses

You are granting permission, not transferring ownership, and the two get drafted as if they were interchangeable. Scope, territory and term are where these fail, usually years later when somebody wants to use the work somewhere it was never licensed for.

Partnership and LLC operating agreements

These govern the relationship between the owners: contributions, distributions, voting, and what happens when one of them leaves. Nothing files them with the state, because formation documents are separate.

Loan agreements and promissory notes

The note carries the promise to repay and the payment schedule. The loan agreement carries the covenants and any security interest, which is the part that decides what happens in a bad year.

Terms of service and clickwrap agreements

Adhesion contracts, accepted by clicking. Courts enforce them where assent is clear and the terms were actually presented, which is why the placement of the checkbox matters more than the drafting above it.

One more classification appears if you sell to the federal government. FAR Part 16 sorts contracts by pricing structure rather than subject: fixed-price, cost-reimbursement, incentive, indefinite-delivery (IDIQ), and time-and-materials or labor-hour. When a contracting officer says "contract type," that's the list they mean.

Three types of contracts cover almost all US hiring, and the paperwork differs for each.

At-will employment is the default in 49 states. Cornell's Wex describes it as an arrangement where either side can end the relationship at any time and for any reason, so long as the dismissal isn't unlawful. Montana is the exception, requiring good cause after a probationary period. At-will needs no contract, which is why offer letters restate at-will status instead of promising a term.

Fixed-term employment is the inverse. The relationship ends when the term expires, and early exit happens only on the conditions the contract itself sets.

Independent contractors carry the risk. The IRS test is common law, with three categories of evidence and no single deciding factor: behavioral control over what gets done and how, financial control over payment method, expenses and tools, and the type of relationship, including benefits, permanency and whether the work is central to the business. We take it apart in independent contractor vs. employee.

Two pieces are still moving. The Department of Labor's 2024 classification rule is still the codified regulation at 29 C.F.R. Part 795, effective March 11, 2024, but DOL says it is no longer applying that rule in its investigations. On February 26, 2026 it proposed rescinding the rule and returning to a modified version of the 2021 analysis, with comments closing that April. Because the rule is still on the books, private FLSA lawsuits are where it can still matter.

On non-competes, the FTC's 2024 rule is not in effect anywhere in the US and not enforceable, after an August 20, 2024 district court order in Ryan LLC v. FTC. The FTC dropped its appeal in September 2025, so treat the rule as dead rather than paused. State law is untouched and varies widely; California bans them outright. See non-compete clause.

Nearly all of them. The ESIGN Act, 15 U.S.C. § 7001, says a signature, contract or record may not be denied legal effect, validity or enforceability solely because it is electronic. UETA does the same at state level, and nearly every state has adopted it.

What ESIGN leaves out sits in 15 U.S.C. § 7003: wills, codicils and testamentary trusts; family-law matters such as adoption and divorce; most of the UCC, though Articles 2 and 2A stay in scope, so sales of goods are fine; court orders and official court documents; notices of utility cancellation, default, foreclosure, eviction or the right to cure on a primary residence; cancellation of health or life insurance; product recall notices; and documents for transporting hazardous materials.

Look at what isn't on that list. Commercial contracts. Across the thirteen types above: all thirteen can be signed electronically, six also need a signed writing, two may need notarization or recording under state law, and none fall inside the § 7003 exclusions.

Two things the statute doesn't do. It doesn't remove a writing requirement, only allows that writing to be electronic, so UCC § 2-201 still catches a $12,000 equipment order. And it leaves notarization alone: where state law wants a notary, you need one, though most states now allow remote online notarization.

What varies is the evidence. A typed name and an identity-verified signature with a tamper-evident audit trail are both electronic signatures under ESIGN, and they aren't equally easy to defend. For anything you'd litigate over, send it for signature through a flow that records who signed, when and from where.

Two questions decide which template you reach for. Are goods involved, since that puts the deal under UCC Article 2 with a different writing threshold and different default warranties? And is this one deal or a repeating relationship, since a repeating one wants an MSA with statements of work hanging off it rather than a fresh agreement every quarter? Get those wrong and the drafting after them is wasted; how to write a contract covers the clauses in order once the form is settled.

Once the type is settled, a template stops being a shortcut and becomes a control: the same liability cap, the same notice period, every time. Our contract templates library covers most of the types of business contracts above.

The harder problem starts after signature. A hundred agreements spread across a shared drive and three inboxes is a portfolio nobody can answer questions about. Which ones auto-renew inside 90 days? Which carry an indemnity you'd regret? That's what contract management software is for, and why a spreadsheet quietly stops working around 50 active agreements. We walk through that process end to end in our contract management guide.

Chaindoc covers the whole path, from drafting to signature to the stored record, on the contract management page.

Start with an inventory, not a policy. Pull every agreement your company signed in the last twelve months and match each one to the 13 types of business contracts above. Most teams find two things: a category handled ad hoc, usually contractor agreements or NDAs, and a few high-value deals with no signed writing behind them.

Then fix in order. Anything inside the Statute of Frauds that isn't signed gets signed this quarter. Anything you sign more than four times a year gets a template. Anything with a renewal date gets a reminder 90 days out, because a missed renewal costs more than a skipped negotiation.

Under 20 people, a shared drive with a strict naming convention and a calendar will hold. Past that it breaks quietly, and you find out when a customer asks for a copy nobody can locate. Chaindoc's pricing is per document, so the bill tracks what you sign.