Give the appendix a question to answer
An appendix is the section of backup slides after the main presentation. Its job is to help you examine a claim in more detail during a conversation or subsequent review. A financial bridge, a cohort breakdown or an architecture diagram can earn a place there when it answers a foreseeable question.
Y Combinator’s Series A guidance recommends preparing slides for investor questions that benefit from a visual answer. It also identifies financial projections and more detailed uses of funds as possible appendix material. That advice is specific to a Series A pitch; it is a useful starting point, rather than a universal slide list for every business.
Write the question before deciding whether to build the slide. “What happens to cash needs if hiring slips?” gives a page a clear purpose. “Extra financials” leaves the reader to work out why it exists.
Source: Y Combinator — How to build a great Series A pitch and deck
Keep enough evidence in the main deck
The main presentation should explain the business and give the audience enough evidence to assess the opportunity. Sequoia’s pitching guide covers areas including the customer problem, solution, market, alternatives, business model and team. Moving all the substance behind these topics to the appendix would leave the main story difficult to evaluate.
Use this editing test: if the reader never opens the appendix, can they understand both the claim and its important conditions? A claim about repeatable demand needs more than a headline and a link to backup. Give the main slide an appropriate evidence summary, its period and any limitation that materially changes the conclusion.
This matters when a positive result depends on a narrow customer group, a proposed plan needs an unresolved permission, or a forecast assumes an untested sales channel. Keep the relevant condition beside the conclusion. The appendix can explain the calculation or background in greater depth.
Keep the conclusion, essential evidence and decision-changing conditions in the main deck. Put the deeper explanation in the appendix. Keep underlying records in an appropriate separate file.
Sort the material into three places
The following table is an editorial framework for reviewing your own material. It is not an investor checklist or a requirement to create every type of slide. The right depth depends on your business, stage and the conversation you are preparing for.
| Subject | Main presentation | Appendix or separate file |
|---|---|---|
| Demand | The relevant result, period, customer basis and material limitations | Appendix: segment or cohort breakdown. Separate file: underlying account-level records when appropriate. |
| Financial plan | The shape of the plan, cash needs and assumptions that drive the case | Appendix: scenario comparison and cost build-up. Separate file: the working financial model. |
| Market | The target customer and a clear basis for the opportunity | Appendix: sizing method, inputs and source dates. Separate file: full research material. |
| Product or technology | What it does, why it matters and its current development status | Appendix: architecture or test explanation. Separate file: detailed specifications or reports. |
| Competition | The alternatives and the differences relevant to customer choice | Appendix: comparison criteria and supporting evidence. Separate file: research notes. |
| Funding request | The amount, purpose, intended progress and important dependencies | Appendix: workstream detail and scenarios. Separate file: detailed budget and relevant supporting documents. |
Work through an example before cutting slides
Imagine a fictional B2B software company whose draft slide says, “Pilot customers are moving to paid contracts.” Its team wants to move the customer-status table to the appendix to make the slide cleaner. This is an illustrative editing exercise, not a Pitchwave or client result.
First, check what the sentence actually claims. A signed paid contract, an active unpaid pilot and an expression of interest have different meanings. The main slide should show enough of that distinction to support the sentence: counts by relevant status, an as-of date and the scope of the group. If conversions come from only one customer segment, identify that limitation where it affects the argument.
Then build a backup slide for the likely question: “Which pilots have converted, and over what period?” A clearly labelled timeline or status table can show the progression in more detail. Use the same status definitions and reporting date as the main slide. An appendix should explain the summary, not introduce an incompatible version of it.
Finally, keep underlying contracts and customer records in the appropriate review materials. A slide can explain the evidence and where it comes from; it does not replace the underlying document. Use only information you are entitled to share in the file being circulated.
If the evidence does not support the original headline, revise the headline. Moving a table out of view cannot fix an unsupported claim.
Make backup slides easy to retrieve
Group the appendix around questions you expect to discuss. Give pages descriptive titles such as “Revenue assumptions by customer segment” or “Deployment depends on the following approvals”. Avoid a sequence of pages called “Additional information”.
Add a short appendix index when the section needs one. Stable labels such as A1, A2 and A3 make it easier to direct someone to a page after you have reordered the main presentation. Where useful, link a main slide to the relevant backup and provide a route back.
Each backup page should make sense when opened directly. State the measure, period, units, definitions and source needed to interpret it. A chart copied from a workbook may need a brief explanation of what has been included or excluded.
Check these routes in the exported file you intend to send. Confirm that links open the correct page and that the appendix remains readable at normal viewing size. If the deck is likely to be forwarded, include the explanation in the file instead of relying on the covering email.
Use questions to maintain the appendix
After a pitch, record the substantive questions that came up. Ask whether each one needs a better spoken explanation, a clearer main slide, a backup slide or a separate document. A repeated question can reveal a gap in the main story; adding another appendix page is only one possible response.
Keep the main and backup slides on the same information basis. When the reporting period, plan or definitions change, update the connected pages together. Remove superseded versions from the file you will circulate, while preserving working history in your own source materials.
There is no useful target ratio between main slides and appendix slides. Build the pages you can explain and support. Remove duplicate material that does not answer a distinct question. If the detail requires searching, filtering or recalculation, a slide may be the wrong format for that part of the review.
Check the appendix before the next meeting
Read the main deck once without opening any backup. Then choose a few important claims and follow their supporting material. This tests whether the argument stands on its own and whether the deeper evidence is easy to find.
When commissioning investor presentation design, share the main deck, existing backup, supporting models and the questions you need to answer. Identify which information is approved for circulation and who owns each source. That makes it possible to improve the structure as well as the slides.
- PurposeDoes each backup slide answer a specific, relevant question?
- CompletenessDoes the main deck retain essential evidence and conditions?
- ConsistencyDo figures, definitions, periods and status labels agree across the file?
- TraceabilityCan you identify the source behind each important claim?
- NavigationCan you find the page, read it and return to the main discussion in the exported file?
- ScopeAre underlying documents kept in a suitable format and shared with the appropriate audience?