There are actually quite a few different online companies that offer editing or proofreading positions. Some of them are freelance positions while others are telecommuting jobs where you work remotely as an employee of the company. Here are a few that you may want to try:
Wordy is essentially a crowdsourcing platform for editing and proofreading. The signup process involves filling out your profile, providing references, and taking a language test. The test contains both multiple choice questions and an on-screen editing test. All in all, the application process takes about an hour. Here is a link to learn more:
This company is a little different in that you register as an editor, adding your credentials and work experience. Once you are added to the editor panel, clients can then select you to edit their work based on the information in your profile. Although there are no specific requirements listed on the site to become an editor, most of the current editors on the site have extensive experience and impressive educational backgrounds. However, the application process looks fairly simple, so it may be worth a shot. Here's a link to the site so you can learn more:
This company offers both part-time and full-time positions for remote proofreaders. The application process involves taking a 20-minute online test. According to their job listing page, they provide competitive pay and flexible hours. You can learn more or apply here:
Book In A Box
Book In A Box is a service that helps people who have a great idea for a book but don't have time to write it on their own. This company regularly hires remote editors to work on these books. This is not a traditional editing job. Instead, it is a bit like a combination of being a journalist, editor, and writer.
As a remote editor, your job is to conduct an interview with the person who wants to write the book to gather relevant information about the topic of the book. This interview is recorded and transcribed. From there, you then have to reword the transcription into a readable format that flows well, is easy to read, and clearly gets the author's point across. If it sounds a bit complicated, it is. However, the position pays extremely well. Not only that but being able to work closely with interesting people can make the job fun and rewarding. You can learn more about the position to decide whether or not it is something you might be interested in here:
Gramlee provides basic editing services for clients starting at $0.02 per word. They offer a 24-hour turnaround time on documents that are less than 3,000 words. Their site says they are always adding editors to their team. The application process is a bit unique. Rather than filling out a traditional application, you simply answer three questions in 200 words or less. The questions include telling them why you are interested in working for them, explaining why you are a good candidate for the job, and demonstrating how you would edit the first two paragraphs on the Jobs page of their website. Here's a link to their Jobs page so you can learn more or apply:
Having never worked for any of these companies myself, I can't vouch for whether or not they pay well or send out payments in a timely manner. However, they all seem to have solid online reputations and are most likely reputable companies to work for. Good luck!