They are not a pair; they are two separate adoptions
Adopting two unrelated adult cats on the same day feels efficient, and rescues often welcome it, but the cats themselves did not choose each other. Each arrives with an adult's fixed habits, sensitivities, and confidence level, and each experiences the other as a rival who appeared in an already strange new territory. That is a very different proposition from a bonded pair or littermates. Success is absolutely achievable — many such duos become friends — but it is built by you, through space and staging, in the first weeks. Plan for tolerance first and friendship as a bonus.
Separate base rooms are non-negotiable
Give each cat their own room at first, each fully equipped: litter tray, water, food, scratching post, bed, and somewhere to hide. Neither cat starts life in your home feeling ambushed, and each bonds with the household's people and routines without competition. Feed them on opposite sides of a closed door once both are eating confidently, so each begins linking the other's smell with meals. Swap bedding between the rooms after a few days, and let each explore the other's empty room, building a scent map before any face ever appears.
Introductions are a dial, not an event
Move in stages and let the cats' behaviour set the speed: door feeding, then a cracked door or gate where they can see without reaching, then short supervised time in the same room with food or play as the focus and an easy exit for both. Hissing at a first sight is communication, not failure; what matters is whether tension eases across sessions. If one cat stalks, blocks doorways, or guards trays, go back a stage and add resources rather than pushing through. A slow introduction that takes three weeks beats a dramatic one that poisons the relationship in an afternoon.
Everything doubles, including the unglamorous parts
Your costs and logistics genuinely double: two initial vet checks, two sets of vaccinations and parasite prevention, and ideally one more litter tray than you have cats, placed in different areas so neither can guard the route to a single tray. Feed in separate spots at first to prevent quiet competition, keep two carriers, and expect twice the hair, twice the play needs, and two different personalities to learn — one may want laps while the other wants a windowsill and to be left in peace. Write down who eats what and who is due what, because details blur fast with two.
Some duos coexist rather than adore, and that is fine
Judge the outcome by calm, not by cuddling. Two adults who eat relaxed, use their trays, share rooms without tension, and only occasionally choose the same sofa have succeeded completely. Forcing closeness — carrying one to the other, or staging photo-opportunities — undermines the peace you built. Keep notes on each cat's preferences and share them with everyone involved in their care, because consistency across people is what makes a two-cat introduction hold. KinsLe's Family Sharing lets the whole household work from both cats' shared profiles and care information, so whoever feeds, plays, or supervises follows the same introduction plan.