A shared sheet solves the two-memory problem
In a two-person household, checkup knowledge usually splits unevenly: one partner books and attends, the other holds a vague impression that everything is up to date. A spreadsheet you both share replaces those two partial memories with one visible table that either of you can open from a phone, at work, or in the practice waiting room. For an annual event this shared visibility is the main prize. The sheet does not ping you like a calendar alert, so it needs a structure that makes urgency obvious at a glance and a routine for opening it, which the set-up below provides.
Columns that earn their place
Give each cat one row, and keep the columns tight: cat name, date of last checkup, next due month, practice and its phone number, vaccines covered at the last visit, weight at the last visit, and a notes column for recheck items and handling quirks. Resist adding more; a sheet that tries to become the full medical record gets updated reluctantly and then not at all. The single most useful habit is sorting the table by next due month, ascending, whenever you touch it, so the cat needing action soonest is always the top row and neither partner has to scan and calculate.
Update on the day, from the waiting room if possible
The rule that keeps a shared sheet truthful is that the visit is entered before the day ends, ideally by whoever attended, while the invoice is still in their hand. Enter the actual date, advance the next due month by a year, record the measured weight, and replace the notes with whatever the vet wants reviewed next time. Because the file is shared, your partner sees the change without a conversation having to happen, and a discrepancy, a row that still shows last year's date weeks after a visit was mentioned, is visible to both of you rather than hidden in one person's filing.
Make the sheet surface itself on a rhythm
A spreadsheet's weakness is passivity: it never interrupts anyone. Compensate by tying it to a monthly moment you already share, reviewing household budgets, planning the month ahead, or ordering food in bulk, and opening the sheet then to look only at the top rows. If the soonest due month is within six weeks and no appointment exists, book it during that same sitting and type the appointment into the notes column so the intention becomes a fact the other partner can see. Some couples also add a simple colour fill to the due cell that deepens as the month approaches, making urgency readable in a second.
Dates in the sheet, documents with the cat
Even a disciplined spreadsheet stores summaries, not evidence: it cannot produce the vaccination card, the lab printout, or the discharge note a new vet, boarding facility, or emergency clinic asks for. Keep the sheet as the household dashboard and hold the documents themselves against each cat in a form either partner can retrieve under pressure. That is the gap KinsLe Pet Passport fills beside the spreadsheet, keeping every cat's records together in a single packet, so a row in your shared table can always be backed up by the paperwork behind it.