Online payment gateways for small business: a guide for accountants and bookkeepers

Published Thursday 11 June 2026

Table of contents

• Why online payment gateways matter for your clients
• How to help clients start accepting payments online
• Types of online payment methods to recommend
• Understanding payment gateway fees and costs
• How payment gateways integrate with accounting software
• Payment reminder strategies for overdue invoices
• Help your clients get paid faster with Xero
• FAQs on online payment gateways

Key takeaways

• Faster payments reduce cash flow risk. Invoices with online payment options get paid significantly faster, giving your clients more predictable cash flow and less time chasing overdue balances.
• Advising on payment gateways is a high-value service. Helping clients choose, set up, and optimize online payment gateways positions you as a strategic advisor rather than a compliance resource.
• Fee structures vary by gateway and method. Guiding clients through cost comparisons, surcharging options, and volume-based pricing adds real value to your advisory work.
• Integration with accounting software saves hours. Payment gateways that connect directly with cloud accounting tools reconcile payments automatically and reduce manual data entry. You can see client finances in real time.

Why online payment gateways matter for your clients

Late payments remain one of the biggest cash flow threats for small businesses. The Federal Reserve's 2024 Small Business Credit Survey found that more than half of small firms struggle with uneven cash flows. Late-paying customers are a consistent driver of those gaps. That makes payment infrastructure a conversation worth having with every client.

Online payment gateways directly address this problem by removing friction from the payment process. When clients add payment links or card options to their invoices, they make it easy for customers to pay on the spot. Xero data shows that invoices with online payment options get paid roughly 20 days faster than those without.

For your practice, this translates into faster invoice turnaround and more predictable client cash flow. Advising clients on accepting payments online is a natural extension of the advisory work you already do. It delivers measurable results your clients can see right away.

How to help clients start accepting payments online

Getting clients set up with online payments is straightforward when you follow these four steps.

1. Assess the client's payment needs

Start by reviewing the client's current invoicing process and payment terms. Look at average invoice size, payment turnaround times, and the types of customers they serve. A business-to-business (B2B) client with large invoices may benefit from Automated Clearing House (ACH) or bank transfer options. A retail-oriented business might prioritize credit card and digital wallet support instead.

2. Choose a payment gateway that fits

Evaluate gateways based on pricing, supported payment methods, and how well they integrate with the client's existing accounting software. Prioritize gateways that reconcile payments automatically and send real-time notifications. Consider whether the client needs in-person payment capabilities alongside online options.

3. Set up invoicing with payment links

Configure the client's invoicing software to include payment links directly on every invoice. This single step often has the biggest impact on payment speed. Make sure the payment options are visible and easy for the client's customers to use.

4. Test and train

Run a test transaction to confirm everything works end to end, from invoice delivery to payment receipt to the payment reconciling automatically. Walk the client through the process so they understand how payments flow into their accounts and how to handle refunds or disputes.

Types of online payment methods to recommend

Different clients need different payment options depending on their customer base and transaction patterns. Here are the main methods to consider when advising clients.

• Credit and debit cards: The most widely accepted method. The convenience drives faster payment and higher completion rates for your clients.
• ACH bank transfers: Lower fees than card payments, often under 1%. Best suited for B2B transactions, recurring payments, and larger invoice amounts where the percentage-based card fees add up quickly.
• Digital wallets: Apple Pay, Google Pay, and similar services offer a fast checkout experience. They work well for clients whose customers pay from mobile devices, and they use tokenized security to reduce fraud risk.
• Payment links: A simple, shareable URL that takes the customer directly to a payment page. These work well in email invoices, text messages, and even social media. They require no technical setup on the client's end.

For most small business clients, recommending a combination of card payments and one or two additional methods gives the best coverage. The goal is to reduce any reason a customer might delay paying.

Understanding payment gateway fees and costs

Fees are one of the first things clients ask about, and the structure can be confusing. Breaking down the components helps clients make informed decisions and avoids surprises down the line.

Most payment gateways charge a per-transaction fee that includes a percentage of the transaction amount plus a flat fee. For card payments, this typically falls between 1.5% and 3.5%. The Consumer Financial Protection Bureau offers guidance on understanding card processing costs, which can help when comparing providers. ACH transfers are generally cheaper, often charging a flat fee or a much lower percentage.

Some gateways also charge monthly subscription fees or setup costs. Others add fees for features like recurring billing or international payments. When comparing options for clients, calculate the total cost based on actual transaction volume and average invoice size. The headline rate alone can be misleading.

Surcharging is another option worth discussing. Some businesses pass card processing fees to their customers as a line item on the invoice. If a client is considering surcharging, check the regulations in their state first. Rules differ, and adding fees to invoices can affect customer experience.

How payment gateways integrate with accounting software

Payment gateways work best when they connect directly with accounting software. Without a direct connection, someone has to manually match payments to invoices. That process is time-consuming and error-prone.

With a connected gateway, payments match against outstanding invoices in real time. This means less manual data entry and fewer errors. You and your clients also get a clearer picture of cash flow at any given moment.

Xero connects with multiple payment services to handle this automatically. When a customer pays an invoice online, it's matched and marked as paid in Xero's accounting software.

Real-time payment notifications are another advantage. You and your clients can see exactly when payments come in, without waiting for bank feeds to update. This visibility makes it easier to follow up on overdue invoices quickly and keep cash flow forecasts accurate.

Payment reminder strategies for overdue invoices

Even with online payment options in place, some invoices will go overdue. A structured reminder process helps your clients recover payments without damaging customer relationships.

Automated invoice reminders are the first line of defense. Set up reminders to go out before the due date, on the due date, and at intervals after. Each reminder should include the payment link so the customer can pay immediately. Tools like Xero's automated invoice reminders handle this without any manual effort from the client.

For invoices that remain overdue after automated reminders, recommend a personal follow-up. A brief, professional email or phone call is often more effective than another automated message. Coach your clients to focus on resolving any underlying issues, not just demanding payment. An overdue invoice often signals a billing dispute or a simple oversight rather than an unwillingness to pay.

You can also help clients set clear payment terms upfront. Include clear terms on every invoice template. Early payment discounts and deposits for large projects also reduce the likelihood of late payments.

Help your clients get paid faster with Xero

Online payment gateways are one of the most practical tools you can recommend to clients struggling with cash flow. Guiding clients through setup, choosing the right payment methods, and connecting payments to their accounting software delivers immediate value.

The Xero Partner Program gives you the tools and support to do this at scale. A free practice subscription and access to Xero HQ put all your clients in one place. Tiered benefits grow with your practice and support the advisory work that sets you apart. Join the partner program and start helping more clients get paid on time.

FAQs on online payment gateways

Here are some frequently asked questions about online payment gateways and how they apply to your advisory practice.

What security standards should a payment gateway meet?

Any gateway your clients use should comply with PCI-DSS (Payment Card Industry Data Security Standard). This ensures that cardholder data is encrypted and handled securely. Most reputable gateways handle PCI compliance on behalf of the merchant. Your clients typically don't need to manage it themselves.

Can clients accept international payments through a payment gateway?

Yes, most major gateways support international payments and multi-currency transactions. However, fees for cross-border payments are usually higher than domestic ones. If a client regularly invoices international customers, look for competitive foreign transaction rates. Make sure the gateway supports the currencies they need.

How long does it take for gateway payments to reach a client's bank account?

Card payments typically settle in one to two business days. ACH transfers may take three to five business days. Some gateways offer instant or same-day payouts for an additional fee. This can be worthwhile for clients with tight cash flow.

Should clients offer multiple payment methods on their invoices?

In most cases, yes. Offering two or three payment options removes barriers and gives customers flexibility. At a minimum, recommend card payments and one alternative such as ACH or a digital wallet. The easier it is to pay, the faster invoices get settled.

How do payment gateways handle refunds and chargebacks?

Most gateways process refunds directly through their dashboard, with the refunded amount deducted from upcoming settlements. For chargebacks, the merchant provides evidence through a dispute process. Advise clients to keep clear records of all transactions and communications.