First off, realize that increasing your response rate takes work.  If you don't want to "bug your clients", or you don't want to "work it", then don't put too much pressure on yourself to get your response rate up.  Think of most open rates for marketing emails.   It's usually around 20% if you are lucky. Similar for surveys. And until you educate your clients, they don't understand the need to reply, and they are also afraid of the multiple page survey.

Here are a few tips, depending on how vested you are to get the responses back:
1. I would recommend making it part of your sales and onboarding process. Make sure all new clients know that you will be sending a one question survey and that is part of your USP.
2. I always emphasize: a. we make it easy for you to communicate to us, b. we won't be a service that starts out great and goes downhill, b/c we are always tweaking our service based on your responses. c. your service technicians are bonused on the survey response rate. We really want your feedback and your service techs want it as well. It's the easiest way to give them a tip.
3. We call all new clients who don't answer. We work off the "no response" list and make follow up calls. This is a great task to give to a VA if you have one. 

    a.  Step 1:  Work off the "No Response" list.  

    b.  Click on the survey ID #, which will open up the survey.  That will give you all the phone numbers, etc.

    c.  Scroll down on that screen and click edit; that will open up the survey so that you can enter client comments, a score, complaint issues (service areas) 
    d.  A sample script if you reach someone:  
"Hi Ms. Jones, this is Martha from Dusting Divas.  I was just calling to check in about your last cleaning (service).  
Client proceeds to tell you how it went.  
4. We resend all surveys after 2 days. (BTW, automated resends are in beta testing now).
5. We use a different survey every month. I don't know if this helps, but it does keep the surveys looking "fresh". https://youtu.be/eHA6XaYJI9Q
6. We look on the client list and sort by latest response/response rate. Anyone who has less than a 50% response rate (that's our number, doesn't need to be yours), we change to SMS surveys.
7.  Lastly, consider running a contest to boost your response rate.  Here are a few examples:
   a.  For every survey returned, the client gets an entry for a monthly drawing.  The prize could be a free cleaning, dinner and a movie, etc.  Make sure to heavily promote the contest, and always announce the winners on social media and vis email.  You want others to see that you really do track and reward.  
   b.  Run a contest with your employees.  You could say one winner or multiple winners.  If one winner, then I recommend a drawing similar to (a).  If multiple winners, set a threshold response rate.  Example:  For all employees who have a response rate of 50% or higher (you need to pick your threshold based on your current results), earn a paid day off on their birthday (just an example...you pick the prize).

This is just an additional tip, not related to the response rate. Just wanted to make sure you all knew about using QDS to track your internal HR issues: https://youtu.be/OjNrZabHLWw