trial_started Event - Upstack Data

Fires when a user begins a free trial. This is the start of your trial-to-paid conversion funnel.

Shopify: Not tracked automatically. Fire it from your trial or subscription system.

JavaScript

window._upstack('track', 'trial_started', {
  accountId: 'acct_abc123',
  planId: 'plan_pro_monthly',
  planName: 'Pro Plan',
  trialStartDate: '2026-02-18T14:30:00.000Z',
  trialEndDate: '2026-03-04T14:30:00.000Z',
  trialDaysRemaining: 14,
  value: 49.00,
  currency: 'USD'
});

Properties

Property	Type	Required	Description
accountId	string	No	Account identifier
planId	string	No	Trial plan identifier
planName	string	No	Human-readable plan name
trialStartDate	string	No	ISO 8601 trial start date
trialEndDate	string	No	ISO 8601 trial expiration date
trialDaysRemaining	number	No	Days until the trial expires
value	number	No	Plan price after the trial, in currency units
currency	string	No	ISO 4217 currency code

When to Fire

After trial signup confirmation
After trial activation in your billing system
After Stripe customer.subscription.created with a trial period

Stripe Webhook

Maps to customer.subscription.created when the subscription has a trial period.

sign_up — For account creation
trial_converted — When the trial converts to paid
subscription_initial_purchase — The first paid subscription charge