Had this error today (ie; the day I posted this), on googling found that when inserting data which is more than the length of allowed character would through this error. But in my case, this wasn’t the issue so thought of sharing this with others. I was trying to update one nvarchar field record through management studio which had 250 character length and I was updated a record which had hardly 20 characters but was throwing this error ‘String or binary data would be truncated’ . So I update the record with Update query and voila! it worked 🙂 Hope this would help someone out there!