How do I invoice clients who pay by ACH in the US?

Invoicing Clients Who Pay by ACH in the US: A Practical Guide for Getting Paid Faster

ACH payments (Automated Clearing House transfers) are one of the most common ways US businesses pay invoices—especially for B2B work, retainers, and recurring services. They’re typically cheaper than card payments, more reliable than checks, and convenient for clients who already pay vendors through online banking. But ACH also comes with its own invoicing rules of thumb: you need the right payment details, clear instructions, smart terms, and a workflow that reduces back-and-forth while keeping your records clean.

This guide walks through how to invoice clients who pay by ACH in the US. You’ll learn what to include on the invoice, how to set terms, how to handle authorizations and remittance, how to reconcile payments, and how to avoid common ACH pitfalls. The goal is simple: make it easy for your client to pay you correctly, quickly, and consistently—while protecting your business and keeping your accounting accurate.

What “Pay by ACH” Means in the US (And Why It’s Popular)

ACH is a bank-to-bank electronic transfer system used widely in the United States. It’s commonly used for payroll direct deposit, bill payments, vendor payments, and recurring subscriptions. When a client says they “pay by ACH,” they usually mean one of two things:

1) They will initiate a bank transfer from their bank or bill-pay system to yours (sometimes called an ACH credit).

2) They want you to pull funds from their account after getting permission (an ACH debit), often used for autopay or recurring billing.

Most freelancers and small businesses deal primarily with the first scenario: the client’s accounts payable department sends an ACH payment after receiving your invoice. Your job is to give them an invoice that includes everything they need to send the payment, plus a structure that makes payments easy to match and track.

ACH is popular because it’s cost-effective, predictable for accounting teams, and can handle large invoices without the card processing fees that can add up on high-dollar transactions. For service-based work and B2B projects, it’s often the default payment method once a relationship is established.

Before You Send Your First ACH Invoice: Set Expectations

The fastest way to avoid slow payments is to set expectations before you ever send an invoice. A surprising amount of “late payments” are really “unclear process” problems—missing bank details, unclear due dates, or confusion about how the client’s payment team needs invoices formatted.

Before invoicing an ACH-paying client, clarify:

• Who processes payment? Ask whether invoices go to the project contact, accounts payable (AP), or a vendor portal.

• What is their payment cycle? Some companies pay weekly, biweekly, or only on specific days. If their cycle is “net 30 but we cut payments on the 15th,” you’ll want to send invoices accordingly.

• What invoice details do they require? Many AP teams require a purchase order (PO) number, vendor ID, or certain line item formatting.

• Whether they need banking details on the invoice (and how they prefer those details delivered). Some clients want banking info on every invoice; others prefer it on file via a secure form.

Once you know their process, you can set your own terms and create an invoice template that matches what they need. This reduces delays and makes you look professional and organized.

What to Include on an ACH Invoice (Essential Fields)

When the client pays by ACH, your invoice needs to do two jobs at once: request payment and provide the information needed to send that payment. While every invoice should include core billing fields, ACH invoicing adds a few specifics that improve speed and accuracy.

1) Standard invoice fields

Even if you’re focused on ACH, don’t overlook the basics. A complete invoice should include:

• Your business name and contact info (address, email, phone if applicable)

• Client name and billing address

• Invoice number (unique and sequential)

• Invoice date

• Due date (or payment terms like Net 15/Net 30)

• Description of services/products with line items

• Quantity/hours and rate (if relevant)

• Subtotal, taxes (if applicable), discounts

• Total amount due in USD

• Late fee terms (if you use them)

These fields aren’t just “nice to have.” They help your client’s AP team validate the charge, code it correctly, and pay it without chasing you for missing details.

2) ACH payment instructions

Clients paying by ACH typically need the following payment instructions to send a transfer:

• Bank name

• Account holder name (exactly as the bank has it)

• Routing number

• Account number

• Account type (checking or savings)

• Optional: SWIFT/BIC (usually not needed for domestic ACH, but helpful for some international payers using US rails)

• Optional: Address of bank (rarely required but sometimes requested by enterprise AP teams)

In addition, you should include a short note telling them what to put in the payment memo. For example:

“Please include Invoice #INV-1027 in the ACH memo/remittance field.”

This single line dramatically improves matching payments to invoices—especially when a client pays multiple invoices at once or sends a payment without emailing you.

3) A remittance request

Remittance is the confirmation details that tell you what the payment is for (invoice number, amount, any deductions, etc.). Some companies automatically send a remittance email; others do not. If you request it on your invoice, you increase your chances of receiving it.

Consider adding:

“Please email remittance details to billing@yourcompany.com when payment is sent.”

If you use invoice24, you can standardize this line in your invoice template so it’s included every time.

Should You Put Bank Details Directly on the Invoice?

Many businesses do, and many do not. The “right” answer depends on your clients and your risk tolerance. Putting bank details on the invoice makes it frictionless for AP teams—especially on a first payment. But if invoices are forwarded around, stored in vendor portals, or accessible to multiple people, you may prefer to share bank details more selectively.

Practical options include:

Option A: Bank details on every invoice

This is simplest and usually results in the least payment friction. It’s common in B2B settings where the client’s AP team needs a document on file.

Option B: Bank details shared once, then “on file” thereafter

You share the details securely (for example, via a secure client portal, encrypted file, or a protected message) and then your invoices say: “ACH details on file. Please reference Invoice #INV-1027.”

Option C: Use a payment link or a client portal for bank details

Instead of printing sensitive numbers on the invoice, direct the client to a secure payment instructions page or portal where they can view the information. This can reduce the risk of details being copied into the wrong hands while keeping it convenient for AP.

Whatever you choose, be consistent. The biggest risk is confusion: a client tries to pay and doesn’t have the right details, then your invoice sits unpaid while they wait for you to respond.

Choose the Right Payment Terms for ACH

ACH payments can settle quickly, but corporate payment workflows can be slow. Your payment terms should match the reality of how your clients pay while still protecting your cash flow.

Common terms for ACH-based invoicing include:

• Due on receipt (often used for small projects or new clients)

• Net 7 / Net 10 / Net 15 (common for small businesses and agencies)

• Net 30 (common for mid-size and enterprise clients)

• Milestone billing (e.g., 50% upfront, 50% on delivery)

• Retainers (monthly recurring invoice paid by ACH)

When setting terms, consider adding early payment incentives or late payment fees if appropriate. For example:

“2% discount if paid within 10 days” or “Late fee of 1.5% per month on overdue balances.”

If you work with larger clients, also ask about their vendor onboarding timeline. Some companies need you set up as a vendor before they can pay. This can add days or weeks to your first payment unless you get ahead of it.

Invoice Numbering and Reference Best Practices for ACH

With ACH, accurate referencing is everything. Unlike card payments, ACH transfers often arrive with limited metadata—sometimes just a short memo line. If you don’t design your invoice for easy reference, you can end up with “mystery deposits” that take time to reconcile.

Use these best practices:

• Make invoice numbers clear and unique. Avoid numbers that look like dates or could be confused with PO numbers.

• Put the invoice number in multiple places. Include it near the top and again near the payment instructions.

• If the client uses POs, include the PO number prominently. Many AP teams cannot pay without a PO reference.

• If the client pays multiple invoices in one ACH transfer, request a remittance email listing included invoices.

If you’re using invoice24, set up a consistent invoice numbering scheme (e.g., INV-2026-0001) and keep it sequential. This is helpful not just for clients, but also for your own reporting and auditing.

How to Structure Line Items for Faster AP Approval

Clients who pay by ACH often have an AP process that includes review, approval, and coding. The clearer your line items, the fewer questions you’ll receive—and the fewer delays you’ll face.

Tips for line items:

• Use plain language descriptions. “Website maintenance (January 2026)” is clearer than “Maintenance services.”

• Match the contract wording. If your agreement says “Monthly SEO retainer,” use the same phrase.

• Separate expenses from services. If you bill travel or reimbursables, list them as separate lines with notes.

• Include date ranges for recurring work. For example, “Support retainer: Jan 1–Jan 31, 2026.”

• Avoid overly long invoices unless necessary. If you have many items, group them and provide details in an attached statement if your client’s process allows it.

AP teams love invoices that are easy to approve. When they aren’t, your invoice can get stuck in a queue while someone asks for clarification—sometimes after the next payment cycle cutoff has passed.

ACH and Taxes: What You Need to Consider

ACH itself doesn’t change your tax obligations, but the way you invoice can affect how taxes are calculated and reported.

Key considerations include:

• Sales tax: If you sell taxable goods or taxable services in certain states, your invoice should show sales tax separately and include the relevant tax rate and jurisdiction details as required.

• VAT: Generally not applicable for US domestic invoicing, but if you work with international clients, make sure your invoice formatting aligns with the applicable rules for the transaction.

• W-9 and 1099: US clients may ask you for a W-9 so they can issue a 1099-NEC if applicable. This isn’t an invoicing “feature,” but it’s part of getting paid smoothly by many businesses.

• Withholding or deductions: Some clients may deduct amounts for reasons like prior credits or contract terms. Ask for remittance details so you can record those correctly.

If you’re unsure whether you should be charging sales tax or how to present it, it’s worth consulting a qualified tax professional for your specific business situation. Your invoice tool can present totals clearly, but you decide what must be included.

Handling ACH Authorization (When You Pull Payments)

Many businesses stick to client-initiated ACH payments. But if you offer autopay or you want to “pull” payments (ACH debit), you need explicit authorization from the client. This typically involves a written agreement where the client consents to you debiting their account for specified amounts on specified dates.

To keep things clean:

• Use a written authorization form that includes the client’s legal name, bank details, authorization scope (one-time or recurring), and cancellation terms.

• Keep the authorization on file in a secure location.

• Confirm amounts and dates prior to initiating debits, especially for variable invoices.

• Provide receipts or payment confirmations so clients have a clear record of what was debited and why.

For many invoice workflows, a simpler approach is to invoice as normal and let clients initiate ACH from their bank. But if you do recurring retainers, autopay can reduce late payments—provided you do it properly and transparently.

Payment Timing: When Will ACH Actually Hit Your Account?

Clients often assume ACH is instant. It usually isn’t. Settlement timing can vary depending on the banks involved and how the payment is initiated. Some transfers post quickly; others take additional business days. Additionally, if a client initiates payment late in the day or before a weekend or holiday, you may not see it until the next business day or later.

To minimize confusion:

• Use clear due dates and specify whether “paid” means “initiated” or “received.” Most businesses define “paid” as when funds are received.

• Send invoices early enough so clients can get them into their payment run. If their AP cycle is weekly, sending your invoice two days before their payment date might mean you wait another week.

• Consider reminders a few days before the due date to prompt scheduling.

In invoice24, you can set invoice due dates and send reminders that help clients schedule ACH transfers on time without you having to chase them manually.

How to Send ACH Invoices: Email, PDF, Portals, and Best Practices

Most ACH invoices are sent as PDFs via email, but there are a few delivery methods depending on your client:

• Email + PDF attachment: Still the most common. Use a clear subject line like “Invoice INV-2026-0007 – Due Feb 15, 2026.”

• Email + link to an online invoice: Convenient for clients who want to view and download.

• Vendor portal upload: Common for enterprises. Your invoice must match their requirements precisely.

• Accounting system integration: Some clients want invoices in a standardized format or sent to an AP inbox with specific rules.

Best practices:

• Keep the email short and scannable. Include invoice number, amount, due date, and what it’s for.

• Attach a clean PDF with all details and ACH instructions (or note “on file”).

• Avoid sending from a “no-reply” address if you want remittance details or quick replies.

• Use consistent formatting so AP teams recognize your invoices quickly.

Small presentation choices can reduce friction. If a client has to hunt for your total or your due date, you increase the chance of delay.

Reminders and Follow-Ups That Work for ACH Clients

ACH-paying clients often need a nudge because payment is usually a scheduled task rather than a quick click. The key is to remind them in a way that fits business norms and respects their AP process.

A simple reminder schedule might look like:

• 5–7 days before due date: Friendly reminder with invoice link/PDF attached.

• On due date: “Due today” note with payment instructions and reference number.

• 3–5 days overdue: Request status and confirm if payment has been initiated.

• 10+ days overdue: Firmer follow-up, mention late fees if applicable, and request a payment date.

Always include the invoice number, total due, and payment instructions in the follow-up. If you’re dealing with a larger organization, send follow-ups to AP (if appropriate) and CC your primary contact.

Invoice24 can automate reminders so you don’t need to remember dates or draft new emails every time. Consistent reminders are one of the simplest ways to improve cash flow without sounding aggressive.

Reconciling ACH Payments: Matching Deposits to Invoices

Reconciliation is where ACH can either be painless or a headache. Because bank deposits may arrive with limited information, you need a system that makes matching easy.

Here’s a reliable workflow:

1) Require invoice numbers in the payment memo whenever possible.

2) Track sent invoices and due dates so you can anticipate incoming payments.

3) When a deposit arrives, match the amount and date to an open invoice.

4) Confirm with remittance details if the payment covers multiple invoices, includes deductions, or differs from the invoice total.

5) Mark the invoice as paid and record the payment date and method (ACH).

If you receive a payment that doesn’t match an invoice amount, don’t guess. Ask for remittance or clarification. Common reasons for differences include partial payments, bundled payments, deductions, or bank fees (less common for domestic ACH but possible with some payment routes).

Invoice24’s tracking tools help you see what’s outstanding and what’s paid so you can reconcile quickly and keep your books accurate.

What to Do When Clients Pay Multiple Invoices in One ACH Transfer

It’s common for businesses to bundle vendor payments into a single ACH transfer. That’s convenient for them, but it can make your reconciliation harder if you don’t get details.

To handle this smoothly:

• Encourage remittance emails listing included invoice numbers and amounts.

• If you have multiple invoices due, consider consolidating into a single invoice when appropriate (and when your client prefers it).

• Keep invoice numbers clear and avoid duplicates or ambiguous formats.

• Maintain a running statement for clients who bundle, showing open invoices and totals due.

If a client regularly pays bundled amounts, you can adapt your process: issue invoices on a consistent schedule and ask their AP team what format they prefer for remittance. Once you align with their workflow, the whole thing becomes predictable.

Common ACH Invoicing Mistakes (And How to Avoid Them)

ACH is straightforward, but there are a few recurring mistakes that slow payment or create confusion.

1) Missing or incorrect bank details

A single wrong digit in a routing number can delay payment and create a chain of emails. Double-check your details before sending, and keep them consistent.

2) No invoice reference instructions

If you don’t tell clients what to put in the memo, you’ll often get deposits with vague notes like “payment.” Always request the invoice number in the ACH memo.

3) Unclear due dates

“Net 30” means different things to different people. Include an explicit due date on the invoice. For example: “Due: March 1, 2026.”

4) Not accounting for vendor onboarding

Large clients may require a W-9, vendor form, or portal registration. If you ignore this, your invoice may be approved but never paid because you’re not set up in their system.

5) Sending invoices to the wrong email

Project contacts aren’t always the ones who can pay. Make sure you have the correct AP email or portal instructions early.

6) Inconsistent invoice formatting

AP teams process hundreds of invoices. Consistency helps them recognize and pay yours faster.

How to Handle Late ACH Payments Without Damaging the Relationship

Late payments happen—even with good clients. The key is to separate “process delay” from “payment issue,” and to stay calm and professional.

A practical approach:

• Start with a friendly check-in. “Just checking whether INV-2026-0007 is scheduled for payment.”

• Ask for a payment date. “Can you confirm the date the ACH will be initiated?”

• Loop in AP if necessary. “I can resend the invoice to your AP team if helpful.”

• Reference your terms. If you use late fees, mention them once politely and only apply them consistently.

• Offer a simple solution. For example, switching to a retainer schedule or setting up autopay for recurring invoices.

Most late payments are solved by clarity and gentle persistence. A clean invoice with clear ACH instructions reduces the likelihood of being late in the first place.

Security and Privacy Tips When Sharing ACH Details

Sharing bank details is normal in B2B invoicing, but it should be done thoughtfully. Keep these practical safeguards in mind:

• Use consistent business banking. Avoid mixing personal and business accounts for invoicing.

• Consider a dedicated receiving account. Some businesses use a separate account for receiving customer payments.

• Limit where bank details appear. If you work with clients that forward invoices widely, consider keeping bank details “on file” instead of on every invoice.

• Watch for phishing attempts. Fraudsters sometimes impersonate vendors and request “updated” bank details. If you ever need to change bank details, notify clients through a trusted channel and consider requesting confirmation via a call.

• Keep records of changes. If your bank account or routing number changes, document when you informed clients and how.

Security isn’t about paranoia—it’s about preventing avoidable problems. A simple, consistent process protects you and your clients.

How invoice24 Can Streamline ACH Invoicing

When clients pay by ACH, your invoicing tool should reduce manual work and eliminate common delays. A well-designed workflow includes all the essentials: professional invoice templates, consistent numbering, due dates, reminders, and clear payment instructions.

With invoice24, you can create invoices that include the information ACH-paying clients typically need, keep invoice details consistent across every send, and track what’s been sent, viewed, and paid. You can also set payment terms and automate reminders so your clients schedule ACH transfers on time.

For recurring clients, invoice24 helps you standardize your process: same format, same instructions, same rhythm. That consistency is what AP teams love—and it’s what helps your invoices get approved and paid without delays.

A Simple ACH Invoice Checklist You Can Use Every Time

Before sending an ACH invoice, run through this checklist:

• Invoice number is unique and clearly visible

• Client name and billing details are correct

• Line items clearly describe what you’re billing for

• Total due is correct and shown prominently

• Due date is explicit (not just “Net 30”)

• PO number/vendor ID included if required

• ACH instructions included (or noted “on file”)

• Memo/reference instruction included (“Include INV-____ in memo”)

• Remittance request included (email address for remittance)

• Delivery method matches client’s process (email, portal, AP inbox)

This checklist prevents the most common payment delays and helps you maintain a clean paper trail.

Final Thoughts: Make ACH Payments Effortless for the Client

When a client pays by ACH, the best invoicing strategy is the one that removes friction: clear invoice details, easy-to-find totals and due dates, straightforward ACH instructions, and a reference system that makes reconciliation simple. Most clients aren’t trying to pay late—they’re navigating their own internal approval steps and payment runs. Your invoice can either help them move faster or become another problem to solve.

If you adopt a consistent ACH invoice format, include strong references (invoice number, PO, memo instructions), and use reminders at the right times, you’ll get paid more reliably and spend less time on follow-ups. And with invoice24 handling your templates, tracking, and reminders, you can run an ACH-friendly process that looks professional and scales smoothly as you add more clients.