It would help knowing what you currently have. Response rates are often highest when it's the least effort to get a response in (like one click on an email your received). But that doesn't provide information you can do something with.
At one company they had a raffle at 1 month, 3 months and 6 months after go live. Anyone with a CSAT completed would join in automatically. Starting a campaign on the wish to improve often helps.
Put a widget on the portal with 'open surveys' so they see it every time they log in.
What doesn't help is reminders. People are already annoyed about every service sending surveys. They need to have a reason to do so.
Please mark any helpful or correct solutions as such. That helps others find their solutions.
Mark
