Paragraph by paragraph
I've designed onboarding and account features at Capital One since 2022, and I'm writing about the Senior Product Designer role at Betterment.
Experience, then the role
He opens with what he designs and where, then names the role. A design manager knows his area before reading further.
The project I'd point you to first is our mobile onboarding redesign. The share of people who abandoned the flow fell by 34%, and completed signups rose by 28%. The biggest change was explaining, on each screen, why we were asking for that piece of information.
One project, with the decision behind it
Two numbers and one sentence on why they changed. The reader learns how he designs, which is what the portfolio interview will test.
Research is a regular part of my week. I've run more than 40 user interviews and usability tests at Capital One, and I built our design system of more than 120 components, which has halved the time it takes to hand a design over to engineering.
Research and the design system
Senior product designers are expected to run research and build shared tools. The handoff figure shows the system made a difference to the engineers.
At Etsy I worked on checkout as a junior designer, and a change I designed raised conversion by 12%. I also built prototypes and ran A/B tests that improved task completion by 21%, and helped ship eight features with product and engineering.
Earlier work, credited carefully
"A change I designed" is honest about his part in a large checkout team. The A/B testing line shows he measures his work.
Betterment helps people make decisions about money that many of them find stressful, and that's the design problem I like most. I check every design against WCAG before it goes to engineering, which matters even more when people are managing their money. I live in Brooklyn and could start in four weeks.
The product, and a reason to want it
A reason tied to what the company does, then his accessibility habit and a start date.
Case studies that get read
Hiring managers skim most case studies and read a few. The ones they read put the outcome near the top and make your part clear.
- The problem, in a sentence, with the number that showed it.
- Your role: what you did yourself and who you worked with.
- What you learned from research, and how it changed the design.
- One or two decisions and why you made them, including what you rejected.
- The result, and what you would change now.
In the letter, name the one project you most want them to open.
For an application form or a message to a design lead
Many tech companies ask a short question on the application form, and design leads are often reached directly. This version answers either.
Design metrics that hold up under questions
Design metrics are easy to inflate, and a design manager will ask how each one was measured.
| Metric | Say alongside it |
|---|---|
| Conversion or completion | Which step, the period, and whether it came from an A/B test or a before and after comparison. |
| Drop off | Where in the flow, and what you changed. |
| Task success in testing | How many participants, and whether it was moderated. |
| Design system | Components, adoption by teams and an effect on engineering, such as handoff time. |
| Reach | Use it for context only. "Across 90 million buyers" describes the size of the product and says nothing about your impact. |
Openings for other UX and product design roles
Junior designer or bootcamp graduate
Lead with one project, real or self initiated, and the research you did for it.
For my final project I redesigned the prescription refill flow for a local pharmacy and tested it with nine of their customers.
Moving from graphic or visual design
Show the user problems you have already worked on and any research you did.
After three years in brand design I have spent the last year on our app’s onboarding screens, including running the usability tests myself.
UX researcher
Give the methods you use and one decision your research changed.
I run around 15 studies a quarter, and last spring our diary study stopped the launch of a feature that most participants misunderstood.
Design systems
Show adoption across teams and the effect on design and engineering time.
The design system I maintain is now used by nine product teams, and new screens reach engineering in half the time they used to.
Design lead or manager
Talk about the team, how you run critique and one result across the product.
I lead six product designers, and this year we set up weekly critique with engineering in the room, and late design changes dropped by about half.
Accessibility in a design letter in 2026
- WCAG 2.2 became the current W3C Recommendation in October 2023. It adds criteria such as minimum target size and accessible authentication, which affect sign in and onboarding flows directly.
- US public sector: the Justice Department's 2024 ADA Title II rule uses WCAG 2.1 AA for state and local government websites and apps. Its deadlines have changed since, so check them if you design for those clients.
- Europe: the European Accessibility Act has applied since 28 June 2025 to many products and services sold in the EU, including banking and ecommerce.
In the letter, say what you do, such as checking contrast and focus states or testing with a screen reader, more than which standard you follow.
Five mistakes in UX cover letters
"User centered" and "passionate about UX"
It says nothing about how you work.
Describe one decision and what led to it.
Borrowing the product’s scale
A big user number describes the company and says nothing about what you changed.
Give the change your work made, with how it was measured.
No research
Senior roles expect you to run research yourself.
Say what you ran and what it changed.
A list of tools
Figma is assumed for UX roles, so listing it adds nothing.
Mention a tool only if the job asks for it.
Pointing at the whole portfolio
A reader with ten minutes needs to know where to start.
Name the one case study to open first.
Length and format for US tech companies
- Length: one page. Marcus's letter is about 215 words.
- Greeting: by name with Ms. or Mr. and a comma, or Dear Hiring Team if you can't find a name.
- Links: the portfolio link on the CV and in the letter's header, tested without a login.
- Tone: plain and specific, the way you would present a project in critique.
The main points from this page
- 1Name the one project you want them to open first.
- 2Give the decision behind each number.
- 3Use metrics with how they were measured, never the product’s total users.
- 4Show research you ran yourself.
- 5Say what you do for accessibility, and know that WCAG 2.2 is current.
Frequently asked questions
What should a UX designer cover letter include?
The role and company, the project to look at first with one result and the decision behind it, the research you run, any design system work, and why you want this product.
Should I include metrics in a UX cover letter?
Yes, one or two, with how they were measured and what you changed. Leave out the product’s total users.
What is the current version of WCAG?
WCAG 2.2, which became a W3C Recommendation in October 2023. Many legal standards still refer to WCAG 2.1 AA.
How long should a UX cover letter be?
One page, around 200 to 250 words, pointing to the portfolio for the detail.
Do I need a cover letter for a UX job?
Not always, but a short one that points to the right case study helps when a hiring manager has many portfolios to review.