Hey Proofers! Here's something I've heard over and over since FIREproof launched: "My spouse and I plan together, so we just share my login." That works, right up until one of you sets up two-factor authentication on your phone, or you each want to try a scenario without the other one stumbling into it halfway built.

So FIREproof now has households. You invite the people you plan with, they sign in with their own email and password, and you each see the simulations the other chooses to share. And here's the part I'm most excited about: your Pro subscription comes along for everyone in your household. One subscription, and the person you plan with gets Pro features on their own simulations too, without paying a cent.

Pro follows the household

This is the foundational piece of the household feature. If you have Pro, everyone in your household gets Pro too:

• Starting a household is a Pro feature. You need Pro to send an invitation.
• Joining is free. The people you invite can join on a free account. There is no per-seat pricing, and nobody else in your household needs a subscription.
• Pro covers everyone's simulations, not just yours. While someone is in your household, Pro features follow your subscription. That's true on the simulations you share with them, and it's true on the simulations they build themselves. A free partner can keep several saved simulations and use Pro settings like bracket-fill withdrawals in their own work.
• Room for up to four people besides you. This can be spouses, kids, parents, whatever. A pending invitation holds a place until it is accepted or withdrawn.
• After your Pro lapses, features stop working. Everyone keeps their access and their simulations, and you can't send new invitations. A simulation someone set up with Pro features won't run until those features are turned off, and the message they see lists each one and where to switch it off. Everything comes back when you resubscribe.

Why this matters for retirement planning

In a lot of couples, one person is "the spreadsheet person" and the other trusts them to have it handled. That's fine until it isn't. Retirement decisions are joint decisions: when to stop working, when each of you claims Social Security, how much you'll spend, whether the house gets downsized. They go better when both people can open the plan, poke at it, and ask "what if we did this instead?" on their own time.

It also matters for the harder cases. If the person who runs the numbers can no longer do it, the other one shouldn't be starting from zero. And households aren't only couples: an adult child helping a parent, a caregiver, or a trusted accountant can all be part of one. FIREproof calls it a "household" on purpose.

Inviting someone

There's a new purple Share with household button under Sim Actions in the sidebar. You can also get there from Household in your account menu. If you aren't on Pro yet, the button wears a small Pro badge, and the Household window explains that inviting is a Pro feature.

1. Type their email address and choose Invite.
2. They get an email with a link. The invitation sits under Pending invitations, where you can resend it or withdraw it. Invitations last 14 days.
3. When they open the link, FIREproof shows them what joining means before they accept anything. They have to sign in (or create an account) with the same email address you invited. If they need to create an account first, they land right back on the invitation afterward.

One small thing before you invite: the invitation email says who it's from, so you need a display name on your account. If you signed in with Google, you already have one. Otherwise, the Household window will point you at Settings → Display Name.

The new sidebar: one list for everyone

Once you're in a household, the simulation list in the sidebar splits into two groups:

• Household holds every shared simulation, from everyone. Simulations someone else made carry their initials, so you can tell at a glance whose is whose.
• Just me holds your own simulations that nobody else can see.

Every simulation stays with the person who made it. Nothing gets copied into someone else's account or transferred away from yours. New simulations you create start out shared, and they're always yours, even if you made them while looking at someone else's.

Joining doesn't expose anything either. When someone joins, the simulations they already had are set to "Just me", and when the first person joins your household, so are yours. Each of you then shares the ones you want the other to see.

"Who can see this sim"

Under the simulation list there's a new Who can see this sim switch with two choices: Household or Just me. It applies to the simulation you have selected, and only the person who made a simulation can change it. On someone else's simulation, the switch is greyed out and tells you who made it.

"Just me" really means just you. A hidden simulation disappears for everyone else in the household, including the person who started the household: it's not in their list, they can't open it, and its edit history stops showing up for them. That's the right place for a half-finished "what if I retire at 50?" idea you aren't ready to talk about yet.

Opening someone else's simulation

When you open a simulation someone else made, it opens in Explorer mode. You can look at everything and run the Proof, but the inputs are locked so you can't change their numbers by accident. A banner across the top names whose simulation it is ("Viewing Alex's simulation"). When you actually mean to make a change, choose Switch to Edit and confirm.

Pro carries over here too. If you're the Pro owner and you open your partner's simulation, every Pro setting is available, and if your partner opens yours, the same is true for them, even on a free account.

Change history

Every change someone else makes to your simulations is recorded: what changed, from what to what, which simulation it was in, and who did it. Open it from the Change history button on the banner. Quick edits to the same field within a few minutes are grouped into one entry, so it reads like a list of decisions rather than a keystroke log.

Anyone in the household can edit a shared simulation, but only the person who made it can delete it.

Privacy, joining, and leaving

• Joining shares nothing you didn't choose. When you accept an invitation, every simulation you already had is set to "Just me." You decide which ones to share, one at a time.
• Leaving moves nothing. The person who started the household can remove anyone, and anyone else can leave at any time, from the Household window. The connection ends right away: they stop seeing your shared simulations and you stop seeing theirs. Nothing is deleted, and each person's simulations and history stay with them.
• Shared means fully shared. Inside a shared simulation there's no partial access: everyone in the household sees every number in it and can change any of them. Invite the people you would show your account statements to, and nobody else.

Try it

1. Make sure you're on Pro and have a display name set.
2. Click Share with household in the sidebar and invite the person you plan with.
3. Once they've joined, pick one of your simulations and set "Who can see this sim" to Household.
4. Have them share one of theirs, open it from your list, and see it with their initials on it.

The Help center has the full details under Getting Started, in "Planning together: sharing your household."

I built this because the best retirement plan is one that both of you actually understand. Now you can each have your own login, your own private scratch space, and one shared set of simulations, all running on a single Pro subscription.

-Lauren

I'm building FIREproof as a solo developer. A Pro subscription keeps the lights on, gets you early access to new features as they land, and now covers up to four other people in your household. If you've been sharing a password with your partner, this is a good time to stop.