The Scenario
You are a sales ops manager. Your team has assembled a spreadsheet of 200 competitor domains and known DNC email addresses, collected from opt-outs, partner lists, and a no-contact agreement signed last quarter.
None of them should ever receive outreach. But right now they are just in a Google Sheet, and every SDR has to remember to check it manually before adding a contact. Nobody does.
The solution is Instantly's block list. But adding 200 entries one at a time through the UI is not how you want to spend your afternoon.
The slow version:
- Log into Instantly
- Open block list settings
- Paste entry 1
- Click add
- Repeat 200 times
- You stop at 30 and hope nobody emails the rest.
The fast version is one prompt.
The Easy Way: One Prompt in SheetXAI
SheetXAI reads your suppression sheet and pushes every entry to Instantly's block list so you do not touch the UI once.
Open the SheetXAI sidebar and type:
Add every entry in column A of this sheet as a block list entry in Instantly — some rows are full email addresses, others are domains — add each one appropriately and write 'blocked' or the error into column B.
SheetXAI reads column A, identifies whether each row is a domain or a full email address, calls the Instantly block list API for each entry, and writes the result into column B. The whole operation runs without you clicking anything inside Instantly.
What You Get
200 entries on the Instantly block list without opening the block list UI:
- Domains blocked — any outreach to addresses at those domains will be suppressed
- Individual addresses blocked — DNC contacts are protected at the lead level
- Column B log — "blocked" for every entry that went in, or an error message for anything that failed
- Instant protection — as soon as SheetXAI finishes, the block list is live
The column B log is your compliance record. If a DNC complaint comes in, you can show exactly when the address was added to the block list.
What If the Data Is Not Quite Ready
Suppression lists collected from multiple sources are rarely in clean shape.
When the list has mixed formats in one column
Some entries are "example.com", some are "@example.com", some are "do-not-email@example.com". Instantly needs them in a consistent format.
Normalize all entries in column A: if a cell contains "@" treat it as an email address, otherwise treat it as a domain. Strip any leading "@" from domain-only entries. Then add each entry to Instantly's block list and write the result into column B.
When you want to split emails and domains into separate columns first
Your compliance team wants the final sheet to clearly separate blocked emails from blocked domains for the audit.
Split column A into two columns: put full email addresses into column B and domains into column C. Then add all entries from both columns to Instantly's block list. Write the block status into column D.
When some entries are already on the block list
You ran a partial import last month. Adding duplicates will error. You want to skip them cleanly.
Add all entries in column A to Instantly's block list. If an entry already exists, write 'already blocked' into column B instead of trying to add it again. Write 'blocked' for new entries and the error for anything unexpected.
When the suppression list comes from multiple tabs you need to combine first
The Competitors tab has domains. The DNC tab has individual emails. The Opt-Outs tab has a mix.
Combine all entries from the Competitors, DNC, and Opt-Outs tabs into one list. Deduplicate by value. Then add each unique entry to Instantly's block list and write the result into a new Results tab with columns for entry, type, and status.
The pattern: normalize, combine, block — one prompt instead of three separate passes.
Try It
Get the 7-day free trial of SheetXAI and open your suppression spreadsheet, then ask it to push everything to Instantly's block list. The Instantly integration is included in every SheetXAI plan. For related workflows, see how to bulk-add verified leads to a campaign or the Instantly in Google Sheets overview.