diff --git a/server/models/boardChannel.js b/server/models/boardChannel.js
index d3b1255..dc4a599 100644
--- a/server/models/boardChannel.js
+++ b/server/models/boardChannel.js
@@ -6,4 +6,6 @@ const boardChannelSchema = new mongoose.Schema({
   tagSlugs: [String],
 }, { timestamps: true })
 
+boardChannelSchema.index({ slackChannelId: 1 }, { unique: true })
+
 export default mongoose.models.BoardChannel || mongoose.model('BoardChannel', boardChannelSchema)