# LongSpan > LongSpan is a retirement planning app for US households who run their own long-range plan without a paid adviser. It forecasts every account, tax bill and big decision to the end of the plan, on Android, iOS and the web. LongSpan shows the forecast and the arithmetic behind it; it gives no financial advice and never moves money. Accounts link read-only through Plaid or are added by hand. A plan can hold 30 account types, and 25 life events can be tried against it side by side before the household decides. Beside the forecast, a Monte Carlo analysis (the market range) runs the same plan through 500 sequences of past US market years (stocks and bonds, Treasury bills, inflation and home prices, read a year at a time) and counts how many its investable savings last through, as a count of replayed markets, not a prediction. Pricing: $4.99 a month or $49.99 a year, one subscription for two partners, with a 14-day free trial. The trial is started in the App Store, Google Play or the web checkout with a payment method, and becomes the paid plan unless cancelled before it ends. Sold in the US only. ## What a plan can hold ### Accounts - 401(k), 403(b), 457(b) and solo 401(k), traditional and Roth - Traditional, Roth, SEP and SIMPLE IRAs - HSAs, 529s and Coverdell ESAs - Brokerage, crypto, savings and CDs - Pensions and annuities - Mortgages, student loans, car loans and credit cards - Linked through Plaid, or added by hand ### Income and contributions - Salary, bonus, self-employment, rental and pension income, each with its own raises - Contributions to each account, with employer match - IRS limits applied, including catch-up contributions - After-tax contributions for a mega backdoor Roth ### Spending - 23 categories, plus your own - Imported from YNAB, or typed in - What's essential, and what changes in retirement ### Equity - RSUs, ISOs and NSOs, on their vesting schedules - Future refresher grants - The year you exercise and the year you sell - A stake in a private business, and its sale ### Home and property - Your home and rentals, with mortgage, property tax, insurance and upkeep - Rental income and costs - The tax break on selling your home ### Kids and college - 529 and Coverdell savings - College costs by school type, from in-state public to private - Private school tuition ### Taxes - Federal tax, and state tax in all 50 states and DC, including a move between states - Payroll and self-employment tax - Capital gains, Social Security and early-withdrawal penalties - Required minimum distributions (RMDs) and Roth conversions - A withdrawal order you can change ### Your assumptions - Returns, inflation and raises, which can change over time - Fees and returns set for each account ## Life events to try against a plan - Buy a house - Sell a property - Rent out a property - Buy a car - Sabbatical - Private school - Inheritance - Extra equity exit - Relocate to another state - Different retirement age - Long-term care - Divorce - Supporting a parent - Large expense - Subscription - Spend more or less - Save more - New job - Job loss or break - Have a child - Market downturn - Claim Social Security - Higher inflation - Renovate a home - Disability ## Questions ### Is it safe to link my accounts? LongSpan links through Plaid, reads balances only and never receives your full account numbers. It can't move money. ### Do I have to link my accounts? No. You can add any account by hand and update its balance when you like. ### Does it give financial advice? No. LongSpan shows the forecast and the arithmetic behind it. The decisions stay with you. ### What happens when the trial ends? Your subscription starts, at $4.99 a month or $49.99 a year, charged by the store you started the trial in. LongSpan emails you 2 days before. If you cancel before the trial ends, you can still open your plan, but you can't change it, and linked accounts are disconnected until you subscribe. ### Can my partner use it too? Yes. The plan holds both your ages, pay and retirement plans, and you can invite your partner to plan with you. ### Which accounts can I add? 30 types, including 401(k), 403(b), IRAs, HSA, 529, brokerage, crypto, pensions, mortgages and loans. ### Does it handle RSUs and options? Yes. RSUs, ISOs and NSOs, with vesting, refresher grants and exercise and sale years, each taxed in the year it lands. ### Does LongSpan run Monte Carlo simulations? Yes. Your forecast holds markets steady at your plan's rates, and the market range is a Monte Carlo analysis of the same plan: it runs it through 500 sequences of what markets actually returned, taken in runs of about 10 years from the US record for 1928 to 2025, in place of your rates. In each year, your investments earn what that year's stocks, bonds and cash returned, your cash earns what Treasury bills did, your home follows home prices, your equity grants follow stocks, and your costs and income follow inflation, with taxes, withdrawals and Roth conversions worked out in every one. It shows in how many of them your investable savings last to the end of your plan, and where your forecast sits among them: near the top if your rates are hopeful, lower if they're cautious. That's a count of replayed markets: it doesn't predict what markets will do. ### What doesn't LongSpan model? It doesn't estimate Social Security, so you enter the benefit from your Social Security statement, and a life event can move it to any claiming age from 62 to 70. A life event can also test a market downturn or a stretch of high inflation. It doesn't model AMT, ESPPs, Medicare premiums or spousal Social Security benefits. ### Can I use it outside the US? No. LongSpan models US accounts and US federal and state tax, and is sold in the US only. ## Use it from an assistant LongSpan is also an MCP server, at https://api.longspan.app/mcp. Once the person connects it, an assistant can read their plan and forecast and try what-ifs without saving anything. It can save scenarios or change the plan only if they allow that in LongSpan. Claude lists it in its [directory](https://claude.ai/directory/longspan), ChatGPT in its [plugins](https://chatgpt.com/plugins/plugin_asdk_app_6aeb984c7d448191ae3338e91abb89df), and [Assistants](https://longspan.app/assistants) says how to connect any other assistant. ## Help ### Setting up your plan - [Who's in your plan](https://longspan.app/help/household): How your birth date, filing status, state, partner and kids shape your plan. - [Your income](https://longspan.app/help/income): How your pay, raises, business income, stock and Social Security are counted. - [Your expenses](https://longspan.app/help/expenses): What to include, what to leave out and how YNAB fits in. - [Your accounts](https://longspan.app/help/accounts): Linked and manual accounts, how each is invested, the market return, fees, contributions and cost basis. - [Property and business](https://longspan.app/help/property): How your home, other property and a share of a business are counted. - [Retirement and assumptions](https://longspan.app/help/assumptions): Retirement age and spending, cash, moves, inflation, tax and Roth conversions. - [How LongSpan chooses your default rates](https://longspan.app/help/default-rates): The long-term rates every plan starts from, their sources, the lifetime mix and how an account earns. ### Using LongSpan - [This year](https://longspan.app/help/this-year): What one year of your plan holds: money in, money out, accounts and tax. - [Cash flow](https://longspan.app/help/cash-flow): Income, spending and what is left to invest, year by year. - [Taxes](https://longspan.app/help/taxes): How LongSpan works out federal, state and payroll tax in each year. - [Net worth](https://longspan.app/help/net-worth): What each part of your net worth counts, and which years the table shows. - [Equity grants](https://longspan.app/help/equity-grants): How your stock and options are counted and taxed in your plan. - [Progress](https://longspan.app/help/progress): How your balances and your plan are tracking against a baseline you saved. - [Market range](https://longspan.app/help/market-range): How your plan holds up across 500 sequences of past market years. - [Settings and your partner](https://longspan.app/help/settings): Planning together, your subscription, and deleting your account. - [Life events](https://longspan.app/help/life-events): What each life event does to your plan, from buying a house to a downturn. ## Links - [Home](https://longspan.app/): what LongSpan does, pricing and the questions above - [Help](https://longspan.app/help): every help page, as listed above - [Assistants](https://longspan.app/assistants): connect Claude, ChatGPT or another MCP assistant to a plan - [Security](https://longspan.app/security): how LongSpan protects a plan and how to report a problem - [Privacy](https://longspan.app/privacy): how a plan is encrypted, used and deleted - [Terms](https://longspan.app/terms): the subscription and trial terms - [Sign up](https://dash.longspan.app/signup): start the free trial