Payments for Concrete Contractors: What Stripe, Square, and the Big Processors Actually Cost You

The short version: concrete runs on deposits before the pour — and the deposit funds the ready-mix, the pump, and the crew before you've collected half the job. A $4,200 deposit on Square's online rate costs $122 in fees; by ACH it's $5. And the commercial side has its own fee math (Level II/III) that flat-rate processors can't touch. Nobody at Stripe or Square will ever write the concrete version of this page. Here's the math at your ticket sizes, with published rates checked October 2026. Also see Concrete & Paving, AI for Concrete Contractors, and Tech for Concrete Companies.

The fee table: what each processor actually charges you

Published rates, checked October 2026. Square: 2.6%+$0.15 in-person, 2.9%+$0.30 online, 3.5%+$0.15 keyed/stored. Stripe: 2.7%+$0.05 in-person, 2.9%+$0.30 online, 3.4%+$0.30 stored. Interchange-plus (typical ISO contractor pricing): ~0.3% markup over interchange.

$1,200 small flatwork (reader on-site): Square $31.35 · Stripe $32.45 · Interchange-plus ~$26.40

$4,200 deposit on $8,400 driveway (online): Square $122.10 · Stripe $122.10 · Interchange-plus ~$92.40 · ACH (0.8%, capped at $5) $5.00

$8,400 driveway, balance on completion day (online): Square $243.90 · Stripe $243.90 · Interchange-plus ~$184.80 · ACH $5.00

$18,000 stamped patio (online): Square $522.30 · Stripe $522.30 · Interchange-plus ~$396 · ACH $5.00

$40,000 commercial paving (invoice, corporate card with Level II/III): Square $1,160.30 (no Level II/III benefit) · Stripe $1,160.30 (no benefit) · Interchange-plus with Level II/III ~$680 · ACH $5.00

$522 versus $5 — same $18,000 patio. The commercial row is the one that matters at scale: Level II/III data (tax amounts, line-item detail) qualifies corporate cards for lower interchange — typically 0.50–1.00% less. Square and Stripe's flat rates pocket the difference; interchange-plus passes it through. On a $40,000 commercial invoice, that's ~$200–$400 per transaction for data your invoicing software fills automatically.

At volume: 100 residential jobs a year at $8,000 = $800,000, plus $600,000 commercial. Residential on Square online: ~$23,240/year; on interchange-plus: ~$17,600/year. Commercial on flat rate: ~$17,400/year; on interchange-plus with Level II/III: ~$10,200/year. Combined savings: ~$12,840/year — the ready-mix for a month. The rails are the same underneath — Finix builds that payment infrastructure; the table is the markup.

The workflow checklist the big processors fail

• Deposits before the pour. 50% down before the ready-mix is ordered — the transaction that funds the job. On a new Square account, a $4,200 deposit is the outlier that triggers a hold. Underwritten accounts price it in advance.
• Balance on completion day. The crew finishes, the homeowner pays — by text link, on the spot. The completion-day glow is the best collection tool; the invoice sent "tomorrow" ages.
• ACH as the default. $4,200 by ACH: $5. By card: $122. "Most of our customers pay by bank transfer and skip the fee" — said at signing, not at completion.
• Commercial invoicing with Level II/III. The $40,000 paving invoice carries tax and line-item data that earns the lower commercial rate. Flat-rate processors can't do this; it's pure margin left on the table.
• Progress billing on big jobs. The $40,000 commercial job bills in thirds against milestones — deposit, pour, completion. Scheduled invoicing, not a send button.
• Surcharging where legal. Most states allow it with disclosure; Connecticut and Massachusetts restrict it. On $18,000 patios the compliant surcharge is meaningful — in the contract.
• Card-on-file at signing. Take the card when the contract signs; charge the deposit when the pour schedules. Stored rates run higher (Stripe 3.4%+$0.30) — the weather-cancellation flexibility is worth it.

Square's pages assume a customer with a card at a counter. Your residential customer has a driveway; your commercial customer has an AP department. Neither is at a counter.

The honest verdict on each processor

Square: fine for small flatwork and the completion-day swipe. Wrong for deposits and commercial at flat rate — $522 on an $18,000 patio is a tax, and it can't do Level II/III at all. Square for the $1,200 sidewalk; something else for the business.

Stripe: the API can do deposits, stored cards, and invoicing — if you build them. Level II/III and commercial workflows are custom. A developer's processor.

Adyen: enterprise interchange-plus with real Level II/III — actually relevant for the commercial side. But enterprise minimums; your $600k in commercial volume is the small end of their attention.

Chase Payment Solutions, Fiserv, Global Payments/Worldpay: quote-based, bank-led, commercial interchange-plus with Level II/III — this is their home turf. The pricing fits both sides of the business; bring your own pour-day workflow.

The concrete answer: interchange-plus merchant account underwritten for $4k+ deposits, ACH as the default for deposits and balances, Level II/III on every commercial card, reader for small jobs. The deposit funds the pour — the processor shouldn't take a cut of the ready-mix.

How a concrete company actually wires this up: notes from Finix's public docs

ClaroPro handles voice-to-invoice — the completion-day balance gets dictated at the truck and billed by text. The money movement is where Finix's public docs (docs.finix.com) get concrete-specific. What to look for:

• Payment links for deposit and balance. Docs cover separate collectible links — the deposit link at signing, the balance link on completion day — so the pour's two halves never share an awkward moment.
• Fee profiles (interchange-plus). Per-merchant pricing structures — the mechanism behind the "$522 vs $5" table above.
• ACH for deposits. Bank-transfer guides with the $5-cap math — the deposit that funds the ready-mix, arriving whole.
• Stored cards at signing. Tokenization docs for taking the card at contract signing and charging when the pour schedules — the weather-cancellation flexibility, with rates visible up front.
• Webhooks for pour events. Payment events that fire when the deposit clears, releasing the batch-plant order automatically — the scheduler knows the pour is funded without the office checking.

Architecture, not brand: underwritten deposits before the pour, ACH default, completion-day balance links, Level II/III on commercial, money events driving the batch order. That's a concrete payments setup.

FAQ

What does processing cost on an $18,000 stamped patio? Square/Stripe online: ~$522. Interchange-plus: ~$396. ACH: $5. Rates checked October 2026.

How do commercial Level II/III rates work? Corporate cards get discounted interchange when the transaction carries extra data — tax amounts (Level II), line-item detail (Level III). Typically 0.50–1.00% cheaper. Flat-rate processors don't pass it through; interchange-plus ones do.

Should deposits go by ACH? Yes — $5 flat vs $122 by card on a $4,200 deposit. The deposit funds the pour; it should arrive whole.

How do I handle weather cancellations with deposits taken? Card-on-file at signing with clear cancellation terms in the contract — the deposit holds the slot, and the reschedule doesn't need a second transaction. Price the stored-card rate in.

This month: get underwritten for $4k+ deposits, move deposits and balances to ACH by default, turn on Level II/III for commercial cards, and collect the balance on completion day. Then read Tech for Concrete Companies — the pour schedule is what makes the deposit timing work.