# What happens when you merge in Dedupely for CSV | Dedupely > The top row in each match group wins. Dedupely gives full control to test logic, apply rules, and clean data before importing, no CRM connection needed. - URL: https://dedupe.ly/blog/merge-in-dedupely-for-csv - Section: blog - Published: 2025-06-13 - Site index: https://dedupe.ly/llms.txt - Any page: append `.md` to its URL for this plain-text form --- [Blog](https://dedupe.ly/blog) Dedupely Insights ## What happens when you merge in Dedupely for CSV The top row in each match group wins. Dedupely gives full control to test logic, apply rules, and clean data before importing, no CRM connection needed. Published June 13, 2025 # min read Merging in a CSV isn’t like merging in a CRM. There are no built-in logic rules, no native associations, and no default “primary” record. Instead, the behavior is defined by one thing: **row position**. In Dedupely, the **top row in each match group wins**. That row’s values will be kept, unless overridden by a merge rule. This gives complete visibility into the merge outcome before it happens, no automation running in the background, no surprises. This also makes CSV mode ideal for testing. You can build a search pad, preview how merges behave, and re-run matches without touching live CRM data. If a rule works, you keep it. If it doesn’t, you adjust and test again. All the core tools apply: merge rules, bulk merge, auto merge, search pads, and custom matching. You also get a downloadable master sheet with all merged records, ready for upload or handoff. The biggest blocker? File format. If headers don’t align or values are mismatched across columns, your merge output won’t be clean. But once structured properly, CSV gives you a predictable, fast way to validate and scale deduplication logic, before it ever reaches your CRM. To merge duplicates in a CSV using Dedupely: - Upload your CSV file to Dedupely - Make sure your file is clean and consistently structured: **headers must match** **across all rows** - Configure match rules to identify duplicates - Adjust the top row in each match group, that row defines the final values - Apply merge rules to editable fields as needed - Export a cleaned master sheet to use or import CSV merging gives complete control, whether you’re testing logic before syncing or cleaning up a standalone dataset. You get editable control, clean previews, and consistent results. No CRM needed. Just a structured file, smart rules, and a repeatable process. For a more detailed walkthrough, [this guide covers our CSV merge process step by step](https://dedupe.ly/knowledge-base/connect-csv). ### Contact us We’d be happy to help you get this set up. #### Write us a message We probably know the answer to your question already help@dedupe.ly Email copied to your clipboard! [Book a Zoom Whether you’re getting started or getting intense. Get in touch! Book a zoom](https://meetings.dedupe.ly/meetings/hampus-isaksson/dedupely-zoom-schedule) ### Discover Related Blog Posts Stay updated with our latest articles and insights. [Dedupely Insights Build a Search Pad system to find all your duplicates How to build a Search Pad system that adjusts match logic per field and finds all your duplicates. Gaby Salinas October 13, 2025](https://dedupe.ly/blog/build-a-search-pad-system-to-find-all-your-duplicates) [Dedupely Insights How to correctly identify all duplicates in your CRM This guide explains how to identify CRM duplicates by using reliable fields, applying match options like exact or fuzzy, testing logic to avoid errors, and. Gaby Salinas September 17, 2025](https://dedupe.ly/blog/merge-with-confidence) [Dedupely Insights The complete guide to Search Pads in Dedupely Search Pads are where you define what a duplicate is in Dedupely: fields, match options and filters. Dedupely August 4, 2025](https://dedupe.ly/blog/search-pads-in-dedupely) [See all](https://dedupe.ly/blog) ### Get started for free 20 free trial merges and as much free support as you need to get your duplicates under control. [Talk to sales](https://meetings.dedupe.ly/meetings/hampus-isaksson/dedupely-zoom-schedule)[Try for free](https://v2.app.dedupe.ly/signup) [Or sign up with Google](https://v2.app.dedupe.ly/signup/google) Running CRM cleanup for clients? [See the Partner Program](https://dedupe.ly/become-a-partner) Skip to content [New Dedupely Intelligence AI deduplication that finds what your rules miss.](https://dedupe.ly/ai-deduplication)