完了 and 終了: completing a process and ending an activity
Compare completed data entry with ended work, including contexts where the work stops while the material remains unfinished.
Completing the specified task or process
完了, read かんりょう, means completing a specified task or process. 必要事項の入力が完了しました。 says that entry of the required information is complete.
The completed process is entry of the required information. This sentence does not also establish completion of screening or delivery.
Ending an activity or procedure
終了, read しゅうりょう, means the end of an activity or procedure. 本日の相談受付は終了しました。 says that today's reception of consultation requests has ended.
時間になったので、作業を終了しました。資料はまだ未完成です。 says that work ended because the allotted time was up, but the material is still unfinished. In this context, ending work differs from finishing the material.
Overlap and a limited scope
Both 完了 and 終了 may be used when the same process is finished. 終了 does not always imply incompleteness; check what the sentence says has ended.
送信は完了しましたが、審査はまだです。 says that transmission is complete, but screening is still pending. Completion of one stage does not establish completion of the entire process.
Does 作業を終了しました。資料はまだ未完成です。 establish that all the material is finished?
Show the answer and why
No. Work has ended, but the material is explicitly described as unfinished.