Is "Please find attached" outdated?

Ways to say it

• I've attached

  NeutralA2

  The plain modern default. Naming what changed, as in the example, does more for the reader than any choice of opening phrase.

  ExampleI've attached the revised statement of work — the change is in section 4 only.

• Attached is

  FormalB1

  Still formal, but shorter and less archaic than "please find". Fits contracts, invoices and anything going into a file.

  ExampleAttached is the signed copy for your records.

• Here's the

  CasualA1

  Internal messages and anyone you speak to regularly. Too light for a first email to a client.

  ExampleHere's the deck from this morning — slide 6 is the one we argued about.

When not to use

Do not swap to the casual forms in correspondence that may be quoted later — legal notices, formal complaints, anything a third party might read out of context. In those threads the slightly stiff register is doing a job: it signals that the message is a record rather than a chat. "Attached is" is the safe choice there, and "Please find attached" is not actually a mistake either.