Netflix has tapped Microsoft as its partner in rolling out an ad-supported service tier.

“Microsoft has the proven ability to support all our advertising needs as we work together to build a new ad-supported offering,” Greg Peters, Netflix’s chief operating officer, said in a statement.

“Microsoft offered the flexibility to innovate over time on both the technology and sales side, as well as strong privacy protections for our members,” he said.

While Microsoft may not have been the obvious pick for a streaming service, the tech behemoth has plenty of experience with both online platforms and ad sales.

For consumers, the big question is how much the ad-supported tier will cost. After all, the whole point of the new service is to attract people turned off by the $15 monthly cost of most ad-free Netflix subscriptions.

Netflix hasn’t dropped any hints about pricing, except to say the ad-supported version will be cheaper than the one without ads.

“Our long-term goal is clear,” Peters said. “More choice for consumers and a premium, better-than-linear TV brand experience for advertisers.”

So let’s put on our wizard hats and peer into the future.

How much do you think Netflix’s ad-supported service should cost? How much will it cost?

My personal feeling is that if you’re going make me watch commercials and make me pay a monthly fee, you need to go a long ways in avoiding the perception of double dipping.

How much should the new service cost? I’ll say $7.50 a month — half the cost of an ad-free subscription.

How much will it cost? I’m betting on a $9.99 (or $9.95) monthly fee.

That’s low enough for Netflix to say it’s competitive with rival offerings from HBO, Hulu and others, but still high enough to generate the revenue Netflix so desperately needs.

The company lost 200,000 subscribers in the first quarter and said it expected to lose another 2 million in the second quarter.

Will an ad-supported tier turn things around? That’s unclear.

Recent surveys have found that most consumers don’t want more than three or four streaming services, especially during difficult economic times.

So Netflix, in seeking new subscribers, has to demonstrate the value of paying a monthly fee to watch ads — particularly to people whose streaming plates may already be full.

It also has to strike the right balance between ads and content (something most other ad-supported streaming services don’t always get right).

Netflix reports its latest quarterly earnings next week. All eyes will be on the subscriber numbers.

And at some point soon, the company will have to reveal the price point for the new service and make the case for why it’s a good deal.