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Hard

Guided Tax Estimate and Payment

Design a jurisdiction-aware flow that estimates a simple tax balance and hands off securely to official payment.

Responsive web

The brief

Understand the problem

Background

Tax calculators can reduce uncertainty, but an estimate depends on jurisdiction, tax year, income type, deductions, and official rules. Payment errors and missed deadlines carry real consequences.

User context

Hana is a salaried worker with one freelance income source. She wants to estimate an outstanding balance, understand the calculation, and pay through the official authority.

Product problem

Taxpayers need a transparent calculation and safe official handoff without mistaking an estimate for a filed return.

Objective

Design eligibility screening, calculation review, payment preparation, and receipt states for one defined tax scenario.

What to design

Define the experience

Required experience

  • Confirm jurisdiction, tax year, and scenario eligibility
  • Enter income and allowed deductions
  • Review calculation lines and source rules
  • Continue to official payment and retain proof

Screens and states

  • Eligibility check
  • Tax inputs
  • Calculation review
  • Payment handoff and receipt

Core user flow

Follow the critical path

  1. 01

    Hana selects her jurisdiction and current tax year

  2. 02

    She enters salary records and one freelance statement

  3. 03

    She reviews the estimated balance and source links

  4. 04

    She pays on the official site and records the confirmation number

Product rules

Requirements and constraints

Requirements

  • Show rule source, tax year, and last updated date
  • Explain every calculation line in plain language
  • Save progress securely without retaining payment credentials
  • Differentiate estimate, filing, and payment completion

Constraints

  • Unsupported tax situations must stop with an appropriate referral
  • Official payment credentials cannot be collected by the calculator
  • Rounding rules must be consistent and disclosed

Reality check

States worth considering

The deadline has passed
Income documents use another currency
A rule changes mid-session
The official payment service is unavailable

Finish line

What to deliver

  • Four desktop-first screens plus one unsupported-scenario note

Optional direction

Visual resources

Use these as a starting constraint if you want one. They are not part of the required solution.

Color palette
#1B1A1A
#E9C5B7
#716561
#8B8C8A
#8C848C
Font pairing
Open SansPrata

Open Sans & Prata

Clear interface writing gives people the confidence to understand what changed and decide what to do next.

Icons
Illustrations