A Customer Portal on Your Own Domain (and When ServiceTitan's Own Portal Is the Smarter Buy)

The phone call a portal exists to prevent

It is 4:40 on a Thursday. A homeowner calls to ask whether she paid the invoice from the water softener install. The office manager finds the job, finds the invoice, reads the balance aloud, promises to email a copy, and goes looking for the PDF. Four minutes. The next caller wants to know when the spring tune-up is due. Then someone wants the warranty paperwork from 2024.

None of these are hard questions. Every answer already sits in ServiceTitan. The only thing standing between the customer and the answer is a person with a headset, and that person was hired to book jobs, not to read records out loud. A portal moves the routine questions to a screen the customer can open at midnight, and gives the office its afternoon back.

There are two ways to provide one. ServiceTitan has its own Customer Portal. Or a portal can live on your own website, with your name on the door, reading from ServiceTitan through its API. Both are legitimate. They suit different companies, and the difference comes down to payments, branding and how much you want to maintain. The other connections a site can make are mapped on the ServiceTitan integration hub.

What ServiceTitan's Customer Portal does out of the box

Be fair to the built-in option first, because for many contractors it is the right answer. ServiceTitan's help center describes the Customer Portal as "a web portal where your customers can view their outstanding invoices, service history, and request appointments," with online payments as an option. Here is what that means in practice, as of October 2026.

• It needs Online Payments switched on, and ServiceTitan Payments for credit cards.
• Invoice and statement emails can carry a payment link, each one unique to a single invoice, so the bill and the way to pay it arrive together.
• Partial payments are allowed, down to a minimum of $1, which helps on larger jobs and financing balances.
• ServiceTitan suggests you "Embed a link to your customer portal on your website," which is the cheapest integration in this whole section: a button in the header and a line on the contact page.
• There is nothing to host or patch. ServiceTitan runs it, and it reads from the records your office already keeps.

If your customers mostly want to pay a bill and check a date, link the portal prominently and stop there. Then check where that link lives today. On plenty of contractor sites it sits in the footer, next to the privacy policy, where no customer has ever looked on purpose.

What a portal on your own site can add, and what it cannot

A branded portal is a set of pages on your domain, in your design, that sign the customer in and then fetch their records from ServiceTitan on the server. The API covers a lot of ground. It also has hard edges, and an honest plan starts with those.

Two rows deserve a second look. Payments first: the branded portal can show the balance, but the money moves through ServiceTitan, so the Pay button sends the customer to ServiceTitan's Customer Portal, or to the payment link already in the invoice email. That means the branded portal works best alongside ServiceTitan's online payments, not instead of them. Second, rescheduling: the API does have PATCH /appointments/{id}/reschedule, but letting customers move appointments without a dispatcher is a business decision before it is a technical one. Most offices prefer a reschedule request they can approve, which keeps the board honest.

When the built-in portal is enough, and when your own earns its cost

The membership case is the strongest. A member who can sign in and see two tune-ups done, one discount applied and the next visit due is a member who renews. Our memberships guide covers selling the plan in the first place, and a portal is where the renewal gets easy.

Security: with a two-legged API, your website is the bouncer

Here is the detail that changes how a branded portal must be built. ServiceTitan's API supports only the OAuth 2.0 client credentials grant, which ServiceTitan calls "two-legged OAuth." The API sees your application, not the homeowner. It will hand your app any customer's invoices if your app asks. So the website, not ServiceTitan, decides who is allowed to see what, and it has to get that right every single time.

• Credentials stay on the server. The client ID, client secret, access token and the ST-App-Key header never reach the browser. A portal that calls ServiceTitan from the visitor's browser is a portal that publishes its keys.
• Prove the customer, then fetch. Sign-in sends a one-time code to the email or mobile number already on the customer's ServiceTitan record, and the session is tied to that one customer.
• Never trust an ID from the browser. The server looks up records for the signed-in customer only; changing a number in the address bar returns nothing.
• Ask for the narrowest scopes. Apps are registered with Read and/or Write scopes, and the contractor's admin reviews them before allowing the app. A portal that only displays needs only Read.
• Cache tokens and data. Access tokens expire after 15 minutes with no refresh token, and the rate limit is 600 calls per 10 seconds per application per tenant. A busy Monday should not hit either wall.
• Log access in plain words. Who signed in, what they viewed, what failed, kept where a person can read it.

How we build a branded portal, from the first meeting to launch

1. 1

   Decide what customers see

   Invoices, visit history, membership status, the plan's included visits. Each screen is agreed with the office, field by field, before any code.

2. 2

   Connect the app in the contractor's account

   API access depends on the contractor's ServiceTitan package. The contractor's admin opens API Application Access, reviews the requested scopes and chooses Allow.

3. 3

   Build sign-in against the ServiceTitan record

   One-time codes to the contact details ServiceTitan already holds, so the portal never invents a second customer list to keep in sync.

4. 4

   Build the read screens

   Server-side requests for the signed-in customer only, cached within the rate limit, with clear wording when ServiceTitan is slow.

5. 5

   Hand off payments and requests

   Pay buttons lead to ServiceTitan's Customer Portal, where online payments live. Appointment and reschedule requests arrive as bookings for the office, queued and retried if a send fails.

6. 6

   Test on a copy of real data

   A ServiceTitan customer's integration environment contains a copy of its production data. Testing there means real edge cases without touching real accounts.

7. 7

   Launch and watch

   Failed sign-ins, slow pages and send errors are watched from day one; Argus in Athena keeps an eye on broken pages and failing forms.

The pattern is not theoretical. For HomeService WebApp, a contractor command center on our work page, DataCram redesigned a tool whose API layer "syncs jobs and estimates bidirectionally with ServiceTitan" and pulls every open estimate, customer and overdue follow-up onto one screen. A customer portal is the same plumbing pointed at a different audience, with tighter locks.

Price, timing and the cheapest first step

Sites with a store, portal or web app start at $3,500, and custom builds without one start at a fixed $1,750, on the web design pricing page. Adding a portal to a site you already have is quoted after a free review. A single two-system connection typically takes one to three weeks per our API integrations page; a portal is several screens on top of that connection, so we scope it before giving a date.

If the portal is part of a larger custom tool, our web app development page covers that work. Not sure where to start? A free site audit looks at what your site does today, and the launch checklist shows where a portal fits among the other connections.