Budget + optimization · in private beta

What's your wallet leaving on the table?

Stack is a budget app that pays you back. Track every dollar coming in. Maximize on every dollar going out. Both halves of your money, one app.

Waitlist opens soon.
A spot in the closed beta is coming. Watch this space.

First 1,000 paid signups become Founding Members at $89.99/yr, locked for life. First 250 can choose Lifetime at $249, one‑time.
30‑day Pro trial included. We'll charge $89.99 on day 30 unless you switch to free or cancel. 7‑day refund, one click. Waitlist gives first invitations, not reserved slots. No credit card to join.

Max · just now
$87 dinner at Carbone. Which card?
USE THE
Amex Gold.
4× Membership Rewards. 348 pts.
Why this over Sapphire? ›
Spend caps · 3 active
Amex Gold · US Supermarkets
$24,200 / $25,000
~2 weeks until cap. Drops 4× to 1×.
Citi Custom Cash · Restaurants
$420 / $500
$80 left at 5% this month.
Freedom Flex · Q4 PayPal 5%
$890 / $1,500
~6 weeks of headroom.
01 · The problem

You've tried to game this system. It's tired you out.

If you've ever stood at a register guessing which card to use, you're the audience. Every one of these is a daily problem you stopped solving years ago. Stack is the budget app built around solving them.

i.
Standing at the register, blank.
Sapphire Preferred for dining, but is this dining? Is the Amex Gold's cap maxed? You picked one, swiped, and immediately doubted yourself. Stack answers in one tap, before you tap.
ii.
The spreadsheet that became a chore.
It started as a clever Notion page. Quarterly categories, 5/24, statement credits, sign‑up bonus thresholds. Now updating it costs more time than the rewards it tracks. Spreadsheet refugees: this was built for you.
iii.
Your Amex airline credit expired Tuesday.
$200 walked away because nothing reminded you. The Saks credit. The Uber Cash. The dining credit. Stack tracks every statement credit in your wallet and tells you in time to use it.
iv.
NerdWallet works for whoever pays them.
"Best card for groceries" is the card with the biggest affiliate payout to NerdWallet. You know this. You've stopped trusting them. We don't weight recommendations by affiliate payout. Ever. (See the pledge below.)
02 · What Stack does

Two questions you're tired of answering. Stack answers them for you.

Most apps focus on your household budget or optimizing your wallet. Stack believes in optimizing the entire budget. Every dollar should be put to work. Especially the expenses.

i.
Which card right now?

The Optimizer.

Ask Stack by tapping, by typing, or just by opening the app. The answer is one card. "Use the Amex Gold." That's it. The points math, the cap headroom, the second‑best alternative if your first card is locked, the merchant category this place actually codes as. All there. All hidden until you tap.

Built for the person who wants the answer. And the partner who just wants the swipe to be right.

One‑tap answer Real bank data No bank link required Manual cards work too
Max · live data
$87 dinner at Carbone. Which card?
USE THE
Amex Gold.
4× Membership Rewards. 348 pts earned.
Why this over Sapphire Reserve? ›
ii.
When does my bonus run out?

The Cap Tracker.

Every category bonus you have, tracked in real time. Amex Gold burning through its $25,000 supermarket cap. Citi Custom Cash 5% category almost maxed out for the month? Freedom Flex with weeks of 5% Q4 headroom left.

Stack does the math. You see the bar. The week your cap is about to die, we tell you.

Live progress bars Estimated cap‑hit dates Per‑card configuration Statement credit reminders
Spend caps · live
Amex Gold · US Supermarkets
$24,200 / $25,000
~2 weeks until cap. Drops 4× to 1× at the line.
Citi Custom Cash · Restaurants
$420 / $500
$80 left at 5% this month, then 1×.
Freedom Flex · Q4 PayPal 5%
$890 / $1,500
~6 weeks of headroom. Plenty.
03 · Why now

Mint died. The replacements forgot the rewards.

Mint shut down in March 2024. 3.6 million people went looking. The replacements raised hundreds of millions to be a better budget tracker. Nobody bothered to ask which card. Stack is the budget app built for the half of the wallet they ignored.

App
Capital Raised
What it does
Mint
~$170M acq · $0 sunset
Free model. Couldn't sustain. Sunset March 2024.
Monarch
$94.8M raised
Beautiful budgeting. Doesn't touch credit‑card rewards.
Copilot
$11.1M raised
Prettiest budget app on iOS. Card‑blind.
MaxRewards
$3.3M raised
Card optimization. No budget tracking.
CardPointers
Bootstrap
No bank link required. Manual everything. Loved on r/CreditCards.
Stack
2026
Both halves of your money. Real data. Honest recommendations.
Birch was right about the product, and wrong about the year.
Stack is right about the product. And right about the year. Stack Market Analysis · May 2026
04 · The pledge
An honest commitment

The recommendation is personal, not paid.

Most rewards apps recommend the card with the biggest affiliate payout. We won't. Stack's recommendations come from your spending, your existing wallet, and your situation. The bank paying us nothing and the bank paying us the most get the same fair shot at the recommendation.

Here's how the money actually works. We're building an Explore Cards feature where you can apply for new cards through Stack. If you choose to apply, the issuing bank may pay us a referral. That's the only time affiliate revenue enters Stack's books. Not at the recommendation step. Not at the Optimizer. Only when you decide to apply.

The line we'll never cross: a recommendation is never weighted by what we'd earn. The card recommended to you is the card that's right for you. Always. If we ever break this, hold us to it.

S
Founder, Stack App
A signed version of this pledge lives in the app, in the footer, and in our terms of service.
05 · Pricing

Pay once a year. Lock it for life.

Founding Members get $89.99/yr, locked for life. No annual increases, ever. First 1,000 paid signups. The first 250 can also choose Lifetime: $249, one-time, never recurring.

Free · forever
$0
A real tool, not a paywall preview. Genuinely useful, free forever.
  • Manual cards (unlimited)
  • The Optimizer. Which card right now
  • 40 Max queries per month
  • Single-month transactions
  • No bank link
  • No Cap Tracker
Start free
Founding Member · most popular
Pro · locked for life
$89.99 /year
First 1,000 paid signups. This price never changes for you. No annual increases, ever.
  • Everything in Free
  • Bank link via Plaid (optional, see FAQ)
  • Cap Tracker. Every card, live
  • Statement credit reminders
  • Multi-month Insights and Trends
  • Unlimited Max queries
  • Vault. Net worth and accounts
  • Founding Member badge in-app
  • 30-day full Pro trial. No charge until day 30
Claim your spot
Lifetime Founder
Pro · one-time
$249 once
No recurring charges, ever. Price guaranteed forever, not dependent on a sale. First 250 paid signups, then closed.
250 slots, claimed at paid signup
  • Everything in Founding Member
  • One-time payment. No subscription
  • Lifetime Founder badge (distinct)
  • Future Pro features included, forever
  • 7-day refund window after charge
  • Available at public launch only
  • Hard cap at 250. No reopening
Reserve a slot

Prefer monthly? $9.99/mo, same Pro features, no Founding Member lock-in. Start a 30-day trial ›

Free 30-day Pro trial
Every paid plan starts with full Pro unlocked. No charge until day 30.
Cancel anytime
Stop your trial before day 30 and you won't be charged. Period.
7-day refund window
Charged and changed your mind? Full refund within 7 days. No questions, no friction.
06 · Questions you'd ask

FAQ.

How does Stack show me what I'm leaving on the table?
Once you link your spending AND add cards to your Stack, we compare what you actually earn on every transaction against what you would have earned using the highest-value card in your wallet for that purchase. The gap across every transaction, every month, is what we call your Missed Rewards. Your number depends entirely on your spend and your cards. We'll show you yours, not a marketing average.
Do I have to link my bank?
No, on any tier. Stack works with cards you add manually, and Cap Tracker, Max, the Optimizer, and the budget all work without ever touching Plaid. The one exception is Missed Rewards, which needs your transaction history to calculate the gap between what you earned and what you could have earned. You have two ways to feed it data: link a bank through Plaid, or enter transactions manually. Linking is the convenience upgrade, not the gate.
What about my data?
Bank-grade encryption. Never sold, never shared. If you do choose to link a bank, Plaid handles that connection. Same plumbing Venmo, Robinhood, and Coinbase use. Read the privacy policy for the full version.
Why $89.99 when Copilot is $95 and Monarch is $99?
Honest answer: we're new, and we're competing on permanence, not on a sale. Founding Member pricing locks $89.99/yr for the first 1,000 paid signups, with no annual increases, ever. After the cap fills, the public price moves to $99.99 to match the category. Competitors sometimes discount below their list price, then raise it again. Stack's Founding Member price is contractually locked the day you sign up.
What's the difference between Founding Member and Lifetime?
Founding Member is annual at $89.99/yr, locked for life for the first 1,000 paid signups. As long as your subscription stays active, that price never changes. No annual increases, ever. Lifetime is $249 one-time for the first 250 paid signups. After 250, the tier closes permanently. Lifetime users never pay again, including for future Pro features. Both come with a 7-day refund window, one click, no support friction. The Lifetime price is contractually guaranteed forever, not dependent on a sale we might end tomorrow.
Is there a free trial? What happens on day 30?
30 days, full Pro access, every feature unlocked. Card on file at signup so the experience is seamless on day 30. On day 30, we charge $89.99 for the annual plan unless you switch to free or cancel beforehand. We send a reminder on day 23 and another on day 28. Both reminders surface three equal options: stay Pro, switch to free, or cancel. Charged by mistake or change your mind? One-click refund in Settings within 7 days. Automated, no support ticket, no retention pop-up. Stack converts because the product worked, not because we made it hard to leave.
When does Stack open up?
Currently in private beta with a small group of power users. Public trial opens later this year. Waitlist signups get the first invitations, and the first crack at Founding Member and Lifetime spots.
Does joining the waitlist guarantee a Lifetime or Founding Member spot?
No. Both tiers are first-come, first-served at the moment you choose a paid plan. Waitlist members get the first invitations to the public trial, which gives you a head start. But the slots fill at paid signup, not at waitlist join. The earlier you convert to paid, the better your odds. Lifetime in particular is hard-capped at 250, ever, with no reopening.
Wait, do you take affiliate money?
Yes, but only at one specific moment. When the Explore Cards feature ships, you'll be able to apply for cards through Stack. If you choose to apply, the issuing bank may pay us a referral. That's the only time affiliate revenue enters our books. Recommendations themselves, anywhere in the app, are based on your data, never on who pays us more. We've made that line public so we can be held to it. Read the pledge above.

Get on the list. First 1,000 are Founding Members.

First 250 paid signups can also choose Lifetime at $249 one-time. Waitlist gives the first invitations, but slots fill at paid signup. No credit card to join.

Waitlist opens soon.
A spot in the closed beta is coming. Watch this space.

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