Begin with the recipient, not the extension
Ask who will open the file and what they will do with it. A person reviewing several related tables may need a workbook. A system import may require one flat table with exact column names. Request the current import template and its field definitions; an example from an old project may no longer match the destination.
Understand what survives a CSV export
Microsoft documents that text formats save the active sheet and lose workbook formatting. CSV is useful for transferring a table, but it is not a complete replacement for a multi-sheet Excel workbook. Keep the workbook separately when its other sheets or presentation matter.
Source: Microsoft Support — Import or export text (.txt or .csv) files.
Agree the meaning of each column
Before exporting, define identifiers, dates, numeric quantities, units and blank values. A code such as 00421 must remain an identifier through the receiving process. State whether an amount includes a currency code or uses a separate field. A delivery note should identify fields whose meaning cannot safely be inferred from their appearance.
- The accepted column names and order
- Which fields are text, dates, quantities or controlled choices
- How missing and unresolved values are represented
- Required delimiter, character encoding and date convention
- Whether one row represents an item, document, person or event
Check both the file and its interpretation
Export a small approved sample and open or import it using the recipient's intended workflow. Compare the values with the source, especially identifiers, punctuation, accented text and dates. A file that looks correct in your usual editor can still be interpreted differently by the destination. Record what was checked and which import behavior remains untested.
Avoid two competing master copies
If you deliver both XLSX and CSV, explain their relationship. For example, the workbook can be the reviewed preparation file while a dated CSV is its import output. If someone changes the workbook afterward, create a new export and revision note. Do not leave two files with different contents both labeled final.
Use a short format decision record
A handoff should make the next action obvious. Note the destination, row unit, expected row count, file revision and known exceptions. Put explanatory notes beside the data rather than inserting a prose paragraph into a CSV table that will be imported. Ask the recipient to confirm acceptance before retiring the preparation copy.
Destination: recipient's approved import template Delivery: CSV + separate field notes Row unit: one supplier product variant Identifier field: ProductCode, text Date rule: YYYY-MM-DD, confirmed source dates only Unknown values: follow the agreed import specification
A few useful answers
Is CSV always better for importing?
No. Use the format and specification the receiving system actually accepts. Some workflows accept workbooks, others require particular text formats.
Will an XLSX file prevent every data error?
No. A workbook can still contain incorrect values, types or formulas. Format choice does not replace source and acceptance checks.
Should I deliver both formats?
Only when they serve a clear purpose. Identify which version is authoritative and when the export was produced so changes do not create conflicting copies.