How to Add a Custom PayPal Checkout Button to Your Website

A PayPal button can look like a small part of your website, but it sits at the point where a customer decides whether to carry on with checkout. If it feels out of place or fails in the live environment, that can become a sales problem.

A custom PayPal button keeps the recognised checkout experience while giving you control over approved styling, layout and placement. The more tailored the flow, the more important it is to test it before customers see it.

This guide explains how to create and customise a PayPal Checkout button, choose the right JavaScript SDK settings, control compatible funding options and test the integration in PayPal Sandbox before going live.

Send Money 💷

Note: Wise Business offers a free Essential plan for basic spending and transferring. If you need to receive money, set up direct debits, or generate invoices, you'll pay a one-time £50 setup fee to unlock the Advanced features.

PayPal custom button at a glance

Choose the right PayPal button setup

Start with the job the button needs to do. A simple, standalone payment action can suit PayPal's button tools. A product or cart checkout that needs its own styling, application logic or callbacks is usually a JavaScript SDK job.

You can start with a prebuilt option and move to the SDK later. The trade-off is simple: less development work usually means less control over the experience around the button.

Create a custom PayPal button with the JavaScript SDK

Create a PayPal app in the Developer Portal, then select either Sandbox or Live on Apps & Credentials.

PayPal displays the client ID and secret after the app is created.³

Use the client ID in the SDK script. Keep the secret and any server-side access tokens out of browser code.

Your implementation needs a target area on the page, the JavaScript SDK loaded with your client ID and currency, button-style settings, and server-side order-creation and capture handling.

Keep the client secret and any access tokens on your server rather than in the page itself.

According to PayPal's JavaScript SDK reference, the order-creation callback starts the checkout flow and the approval callback runs after the buyer approves the transaction.¹

The same reference shows a server-side pattern for creating and capturing orders.

Style the button without breaking PayPal's rules

The SDK's style settings give you useful visual control, but they are not a blank canvas. Use one of PayPal's supported values rather than trying to override the button with arbitrary CSS.

The container still matters. PayPal's SDK adapts the button to the container by default.¹

Set the surrounding element's width and responsive behaviour in your site's CSS rather than trying to force every dimension through the SDK.

Control the payment buttons buyers see

PayPal determines the eligible button set for each buyer. Country, device type and the funding sources a buyer has chosen can all affect what appears.¹

Treat the visible button stack as a live checkout outcome, not a fixed design asset.

You can prevent a funding source from appearing with PayPal's disable-funding setting where it is supported. For example, it can be used to exclude a Pay Later option.

If you need a standalone payment method, according to PayPal's standalone-buttons guidance, configure the button's funding source through the SDK.⁴

Check the current documentation and test the customer markets you serve before assuming a particular button will be shown.

Test the custom button in PayPal Sandbox

Treat Sandbox as part of the build, not a final cosmetic check. It is where you find mismatched client IDs, incorrect order totals and missing success or cancellation handling before a customer does.

1. Create or select a Sandbox app in the Developer Portal and copy its client ID. According to PayPal's credential guidance, Sandbox is for testing and Live is for production.³
2. Load the button with the Sandbox client ID and confirm the script and target container both load on the page.
3. Run a completed checkout, a buyer cancellation and an error scenario. Check the order ID, amount, currency and fulfilment hand-off each time.
4. Repeat the tests at the widths and devices your customers use. Button layout and eligible funding options can change by device and buyer context.¹
5. Move the app to Live only once the live client ID, server credentials, order handling and post-payment confirmation are ready. According to PayPal's credential guidance, you can then move the application to Live.³

Fix common PayPal custom button problems

Check currency conversion costs after checkout

Customising the button changes the checkout experience; it does not change the fees or currency-conversion treatment attached to the payment.

According to PayPal's UK seller-fees page, conversion for a business account balance is currently 3% above the base exchange rate.⁵

The same rate can apply to a transaction where the receiver agrees to bear the conversion.⁵ Check the current fee page before making a commercial decision.

If you receive or hold currency in PayPal, read our guide to changing currency on PayPal Business in the UK before deciding when to convert.

That is a separate decision from the design and implementation of your Checkout button.

Manage the International Costs Behind Your Custom PayPal Button With Wise Business

---

💡 If your custom PayPal button sits on a website that sells internationally, Wise Business can help with the costs behind those orders.

You can send money to overseas suppliers, contractors and fulfilment partners with the fee shown before you transfer, then convert at the mid-market exchange rate with low, transparent fees.

---

Wise Business offers a free Essential plan for basic spending and transferring. If you need to receive money, set up direct debits, or generate invoices, you'll pay a one-time £50 setup fee to unlock the Advanced features.

With Wise Business, you can:

• 🌍 Send money to 70+ countries and pay overseas invoices at the mid-market exchange rate with low, transparent fees and no hidden exchange rate markups (product availability varies by region)
• 📥 Receive payments in 24 currencies and counting
• 💵 Get local account details for 8+ currencies, including USD and EUR, to let your customers pay in a currency they know and trust - convenience for them and peace of mind for you
• 💰 Hold money in 40+ currencies
• 🔁 Convert currencies anytime at the mid-market exchange rate with low, transparent fees
• ⚡ Use the batch payments tool to create and send up to 1,000 payments in a single transfer
• 👥 Run payroll and make international payments for up to 1,000 employees all over the world - including paying suppliers using local payment methods like ACH, SEPA, and Faster Payments
• 💳 Get business debit cards with 0.5% cashback for you and your team to keep track of team expenses and spend all over the world, with real-time visibility and categorisation. See full cashback terms and conditions
• 🏢 Manage cash in 55+ currencies across international offices from a single business account and move money between business accounts in seconds (exact speeds can vary depending on individual circumstances and may not be the same for all transactions)
• 🧾 Connect and sync every business transaction to your favourite accounting software, including Xero, Quickbooks, and more
• 🔐 Create your own payment approvals process to manage your team better with customised access for different team members, roles and permissions
• 📑 Create custom professional invoices and schedule invoice payments for future dates
• 📈 Earn variable returns on GBP, USD and EUR with Wise Interest (Growth not guaranteed. Your balance will go down in the event of a government default or interest rates going negative.)
• 🔗 Create payment links and QR codes to get paid easily (Card payment acceptance for new Wise Business customers is currently unavailable. Payment methods subject to eligibility and availability.)
• ⚙️ Automate payouts with the Wise API (comes with 24/7 customer support, a sandbox account to test integrations, API tokens, and clear documents on how to implement and make the most of our API)

Make the wise choice when selecting a business account for your domestic and global needs.

Be Smart, Get Wise.

Register for Wise Business ✍️

Wise Interest disclaimer: Growth not guaranteed. Your balance will go down in the event of a government default or interest rates going negative. Taxes may apply. 3.32% variable rate on GBP is based on 7 day performance as of 05 Aug 2026. For full 5-year past performance and fund information, visit https://wise.com/interest. Investments are offered by Wise Assets UK Ltd. (FRN 839689)

FAQs

Can I customise a PayPal button on my website?

Yes. According to PayPal's JavaScript SDK reference, button style options include layout, colour, shape, height and label.¹

Can I make a PayPal button any colour I like?

No. Use PayPal's supported presets rather than an arbitrary custom colour. According to the current SDK reference, these are gold, blue, silver, white and black.¹

Can I create a custom PayPal button without writing a full checkout integration?

Potentially. A prebuilt PayPal button or payment-link route may be enough for a simple payment action.

Use the SDK when you need the button to sit inside your own Checkout experience and connect to your own order logic.^1,2

Should PayPal orders be created and captured on my server?

For a production checkout, use the server-side pattern in PayPal's current SDK reference to create and capture orders.¹

Do not treat a browser-only example as the finished payment implementation.

Sources:

1. PayPal JavaScript SDK Reference
2. Customize Checkout and Buttons
3. How Do I Create PayPal REST API Credentials?
4. Customize Standalone PayPal Payment Buttons
5. PayPal Merchant Fees - Seller Fees | PayPal UK

Sources last checked on 27th July 2026