Deep Dive• 5 min read

UPI Payment Links Explained: Syntax & Parameters

Q: What are the mandatory query parameters in a upi://pay URI?

Under official NPCI specifications, pa (Payee Virtual Address / UPI ID) and pn (Payee Legal / Display Name) are strictly mandatory. All other parameters such as am (amount), tn (transaction note), cu (currency), and mc (merchant category code) are optional.

Q: How does intent dispatch work on Android for upi://pay links?

When a user taps a link with the upi:// custom scheme, Android queries the device's PackageManager for all installed applications that declare an <intent-filter> for the android.intent.action.VIEW action with scheme upi . The OS displays an App Chooser sheet allowing the user to select PhonePe, Google Pay, Paytm, BHIM, or any other installed banking app.

Q: Do I need a payment gateway account or API key to create UPI links?

No. Standard upi://pay links require no payment gateway accounts, merchant agreements, or API keys. They leverage the open, decentralized UPI URI protocol supported by all Indian financial institutions.

A developer reference and merchant guide to the upi://pay URI scheme, operating system intent dispatching, and messaging app compatibility.

What is a UPI URI?

Just as web links use https:// and emails use mailto:, the Unified Payments Interface registers a custom protocol scheme named upi://pay with mobile operating systems.

When a user clicks a UPI link on a mobile device, the operating system's intent chooser displays all installed applications that have registered to handle the upi protocol scheme (such as PhonePe, Google Pay, Paytm, BHIM, or bank apps).

Detailed URI Parameter Specifications

A standard UPI payment link is composed of key-value pairs formatted as standard URL search query parameters:

upi://pay?pa=store@okhdfcbank&pn=Tech%20Store&am=499.00&cu=INR&tn=Order%2098231

Key	Status	Specification & Format
pa	Required	Payee VPA/UPI ID (e.g. `name@bank`). Must be URL-encoded.
pn	Required	Payee display name (e.g. `John%20Doe`). URL-encoded spaces.
am	Optional	Amount in rupees with up to two decimal places (e.g. `150.00`).
cu	Conditional	Currency code. Must be `INR` whenever `am` is defined.
tn	Optional	Transaction note or reference (e.g. `Invoice%20101`). Maximum 50 characters.
mc	Optional	Merchant Category Code (MCC) 4-digit numeric code assigned to business accounts.

Platform & Messaging App Compatibility

Android Behavior

Android has first-class native support for custom URI schemes. Tapping a upi:// link in Chrome, SMS, or WhatsApp instantly launches the system app-chooser showing all available payment apps.

iOS Behavior

On iOS, Safari and WhatsApp handle custom schemes when explicitly configured by apps. However, desktop browsers (macOS / Windows) do not have UPI apps installed, so providing a scannable QR code alongside payment links is best practice.

Create Payment Links Instantly

Use our dedicated, browser-side UPI Payment Link Generator to create clean, properly encoded links ready to paste into WhatsApp, SMS, or invoices.

Frequently Asked Questions

UPI Payment Link Questions & Answers

What are the mandatory query parameters in a upi://pay URI?

Under official NPCI specifications, pa (Payee Virtual Address / UPI ID) and pn (Payee Legal / Display Name) are strictly mandatory. All other parameters such as am (amount), tn (transaction note), cu (currency), and mc (merchant category code) are optional.

How does intent dispatch work on Android for upi://pay links?

When a user taps a link with the upi:// custom scheme, Android queries the device's PackageManager for all installed applications that declare an <intent-filter> for the android.intent.action.VIEW action with scheme upi. The OS displays an App Chooser sheet allowing the user to select PhonePe, Google Pay, Paytm, BHIM, or any other installed banking app.

Why do upi://pay links fail to launch on desktop computers?

Desktop operating systems (Windows, macOS, Linux) do not possess native UPI banking applications registered to handle the upi protocol scheme. Clicking the link on desktop browsers triggers an unhandled scheme notice. The recommended best practice is to pair every payment link with a scannable QR code for desktop viewers.

Can I customize the currency parameter (cu) to USD or EUR?

No. NPCI specifications mandate that standard domestic UPI transactions operate in Indian National Rupees (cu=INR). Even for international merchant acceptance (such as in Singapore, UAE, or France), underlying settlement across banking rails is cleared in INR.

Can UPI payment links be shared on WhatsApp and Telegram?

Yes! On mobile versions of WhatsApp, Telegram, and SMS, standard upi://pay?... links are automatically recognized as clickable deep-links that launch installed payment apps with a single tap.

Do I need a payment gateway account or API key to create UPI links?

No. Standard upi://pay links require no payment gateway accounts, merchant agreements, or API keys. They leverage the open, decentralized UPI URI protocol supported by all Indian financial institutions.