Thinks
- What changed?
- What am I missing?
- Are there hidden fees?
In this case study
Overview
- Role
- Lead Amdocs Product Designer
- Timeline
- 2022 — 2023 · Design phase
- Scope
- Digital billing and PDF bill templates
- Team
- T-Mobile Customer Experience and Customer Care, bill architects and developers, with accessibility, brand, legal and product stakeholders
T-Mobile’s bill brings together plans, devices, services, credits and charges across an entire account. The challenge was to help customers understand what they owed, what had changed and what to do next.
I led the experience design across digital billing and PDF bill templates, connecting the information architecture, customer-facing explanations and production rules. The business objective was to reduce avoidable billing enquiries and build confidence in the bill.
The digital experience lets customers move from an overview into more detail. The PDF follows the same underlying structure in a fixed document, with clear summaries, category breakdowns and contextual messages.
My account → View billBill overview
BalanceDue dateAccount status
Understand changes & savings
What changed? What did I save?
Review account activity, discounts and savings before exploring individual charges.
- Help prevent bill shockExplain changes clearly and answer questions before customers need to call.
- Make savings visibleReinforce the value of the plan to support customer confidence and retention.
Explore charges
Two ways to view the bill
Follow the people on the account, or see where the money goes.
- Balance forward
- Account
- Individual lines
- Balance forward
- Plans
- Equipment
- Services
- One-time charges
Take action
Next steps, close at hand.
Payment options stay available from the bill overview.
- Make a paymentPay the current balance.
- Set up a payment arrangementManage how outstanding charges are paid.
- Manage AutoPayManage recurring bill payments.
The problem
The earlier billing approach exposed the account’s complexity before explaining it. Customers had to connect totals, individual charges and account changes to understand why they were being asked to pay.
- What do I owe, and when?
- What changed since my last bill?
- Which person, device or service created this charge?
- What can I do from here?
The redesign needed to answer those questions in a predictable order. First bills, overdue balances, credits and plan changes also needed explanations that matched the customer’s situation.
A digital screen could reveal detail progressively. The PDF had to maintain that clarity across columns and pages, including a meaningful reading order for assistive technology.
Designed for real billing scenarios
The templates and message rules had to cover the full billing lifecycle, including:
- First bills
- Regular monthly bills
- Past-due balances
- Credit balances
- Partial payments
- Adjustments and one-off charges
- Device repayments
- Plan or service changes
- Multiple lines and account owners
- Final bills
- Contextual and live-area messaging
My role & constraints
I owned the billing information hierarchy, navigation, explanatory messaging and translation between digital and PDF. I worked directly with T-Mobile’s bill architects and developers through specification, implementation questions and design QA.
My focus was the billing experience. The surrounding account-management interface and app navigation shown in some examples provide product context. T-Mobile stakeholders contributed the billing, brand, legal and accessibility requirements.
Three constraints shaped the work:
- Variable account data: one template had to handle multiple lines, devices, credits, overdue balances and changing services.
- Fixed PDF production: content limits, table structure and page breaks had to be specified alongside the layout.
- Shared meaning across formats: totals, section names, messages and reading order had to remain understandable as the presentation changed.
What we learned
I worked from existing customer research and Customer Care insight, using the billing scenarios and account flows to turn recurring needs into design requirements. My contribution was to connect those inputs to the hierarchy, navigation and explanation rules across both formats.
Jordan brings those recurring needs together as a representative household-plan owner. The scenario makes the design priorities easier to follow.
JordanHousehold plan owner
- Multiple lines
- Device payments
- Promotions & savings
Feels
- Confused
- Overwhelmed
- Anxious
Does
- Checks charges
- Searches for help
- Calls support
Says
- Explain this fee
- Break it down
- Show me changes
What this meant for the design
- Explain changesBeside the affected charge
- Lead with the essentialsTotal and payment status first
- Offer two viewsBy line and by category
Customers need orientation before detail
Imagine opening your bill and seeing that the total has changed. You want to know what you owe, when it’s due and what made this bill different.
Existing customer research and insight from Customer Care helped me put those questions in order. I made the amount due and due date the starting point in both formats, then placed explanations beside the charges they relate to.
In the examples below, annotation 1 shows where the balance and due date appear on the Digital and Paper tabs. On Paper, annotation 3 shows how the PDF explains a change beside the affected charge.
One breakdown cannot serve every customer
Some customers think about the people and devices on their account; others think about plans, equipment and services.
I kept both line and category routes into the same charges. This gave Customer Care and customers shared reference points without changing the underlying totals.
The explanation has to survive the format
Proximity and indentation can connect information visually, but those relationships also need to work in a fixed document and a logical reading sequence.
I treated headings, section names, grouped charges and message placement as structural decisions. PDF production guidance needed to describe how content should flow as well as where it should appear.
Digital bill
Paper bill
Key decisions
Decision 01Design a template system for variation
- The challenge
A single, category-first breakdown would not suit every customer. Creating unrelated line and category experiences would introduce competing hierarchies and increase the risk of inconsistent totals.
- The decision
I kept two routes into one billing structure: by line for people and devices, and by category for types of spending. Shared section names, totals and charge relationships carried through to the PDF, arranged as summaries and detailed tables.
- The trade-off
Supporting both routes added navigation and specification work. I accepted that complexity in the template rules so customers could use the view that made sense to them.
- What changed
The bill could support different ways of investigating charges while retaining one consistent account structure.
Decision 02Make complex billing circumstances explicit
- The challenge
A plan change can create a refund and a new charge on the same bill. Showing the transactions without their relationship leaves the customer to explain the difference.
- The decision
I placed scenario-specific explanations beside the affected category, distinguishing account activity, mid-cycle changes and regular charges. The same message logic carried into the PDF, with presentation adapted to its fixed layout.
- The trade-off
Every explanation takes space. I prioritised messages by relevance and defined content limits so unusual scenarios could be explained without overwhelming a routine bill.
- What changed
Customers were given an explanation of the account event before being asked to interpret its individual charges.
Decision 03Define layout, logic and messaging together
- The challenge
A polished template could still fail when a message was too long, several conditions applied together or content crossed a page boundary.
- The decision
I worked with bill architects and developers to document the layout, data dependencies, display rules, message priorities and content limits together. Live areas were defined for contextual service and promotional content, with billing information taking priority.
- The trade-off
This required a more detailed handoff and review across teams. Resolving those conditions in the specification gave implementation and QA a shared reference.
- What changed
The handoff described how the bill should behave across scenarios, as well as how it should look. The original artifacts below show the layout limits, field rules and messaging decisions.
Live-area specifications
Logic & rules
Messaging specification
The final experience
The final design connects a clear bill overview with detailed charges and past bills. Digital screens support exploration; the PDF brings the same information into a structured document.
The examples below show the billing work in context. Customer details, amounts and dates are sample data.
Results & impact
The redesigned bill brought a shared structure to digital and PDF, with clearer totals, contextual explanations, visible savings and consistent ways to explore charges. The layout, logic and messaging specifications gave production teams a shared reference for handling varied account data.
120k
Fewer billing calls
~$960k
Lower handling costs
78%
Bill comprehension
Reflection
This project showed how closely a bill’s layout depends on its data, logic, language, accessibility and production rules. At T-Mobile’s scale, a rare edge case can still affect many customers.
Digital and PDF bills needed a shared structure, with each format using its own strengths. Defining headings, labels and a logical reading order made the relationships between charges explicit across both formats.
The lasting value was a set of templates and rules that could turn varied billing data into an experience customers could understand and act on, while supporting relevant service and commercial messages.
