The useful question is not which format looks more professional. It is what the recipient needs to do next. Reading a menu, calculating from a budget, and rewriting a proposal are different tasks. Sending every available format can create confusion rather than flexibility, particularly when nobody knows which copy represents the agreed release.
Reading, reviewing, or continuing the work
A PDF is often suitable for a fixed release with deliberate page breaks: an approved event program or instructions that refer to particular page numbers, for example. It is not automatically accessible or impossible to edit. Depending on the software, its contents may still be copied or changed.
Someone who must adjust formulas, reorganize paragraphs, or reuse slides will generally need the relevant source file. An exported budget shows results without necessarily carrying the calculation workflow the next person needs. Agree on the application and format as well. Two editable formats may handle the same layout or feature differently.
When two files are justified
A design handoff may reasonably include both the source and a PDF. The source enables editing, while the PDF records the intended appearance. Give them matching release names, such as room-plan-v04.docx and room-plan-v04.pdf. Add a short note explaining which file can be changed and which records the approved release.
Inspect the whole source before sharing it. Comments, hidden worksheets, earlier drafts, and embedded objects can contain information absent from the visible PDF. Do not clean your only working copy indiscriminately. Make a separate handoff copy and inspect that version again, including information outside the currently visible page.
Fonts, photographs, and templates may also have limits on redistribution. Explain any missing components and how the recipient can obtain them instead of attaching every supporting file without checking. When someone needs only a few figures, a carefully selected data table may serve them better than the complete project workbook.
State the next step
A note such as 'Please comment on the wording; the PDF is the layout reference' prevents people from editing different files in parallel. For an important handoff, ask for a brief opening test. Being able to open the file and being able to perform the intended work are separate checks.
After a revision, reconcile the paired files again. An updated document beside an outdated PDF is an incomplete handoff. Retain the previous release in an identifiable archive and state which new release replaces it. The extra clarity is especially useful when an attachment is later forwarded without the original conversation.