The target cost bid strategy is the best way to maintain a stable cost per result that your ad set is optimised for while increasing your budget. (This is sometimes called "scaling".) However, there are other choices that you can make to help maximise the effectiveness of this bid strategy. If you follow the recommendations below, you'll be well-positioned to maintain your desired cost target for as long as possible.

This article is intended for people who've found success with their ad campaigns and are looking to start using the target cost bid strategy to scale or increase their spend on it.

Set a sustainable cost target

Consider starting with the ideal average cost that you'd like to pay and increasing it from there as needed. We recommend adjusting until you find the lowest amount you can set that still gets consistent ad delivery and spends your full budget. Bear in mind that this amount may need to be increased from previous successful campaigns if your budget increases are significant enough, as we'd need to win significantly more auctions to spend significantly more.

Tip: A good time to check to see if an adjustment is necessary is after your ad set has completed the learning phase (received about 50 of the result it's optimised for). This will give you a pretty accurate sense of how your ad is performing. If you decide that a significant cost target adjustment is necessary, make sure that you let your ad set get about another 50 of the result it's optimised for after making the change. If you don't, you're not giving our system a chance to optimise delivery based on the new cost target.

Create a strong campaign structure

When increasing the scale of their campaigns, some advertisers spread their increased budgets across more and more ad sets. We don't recommend this. Only create a new ad set if you value reaching different parts of your target audience differently. For example, say you're optimising for conversions and there are two audiences you want to reach:

• A Lookalike Audience of the people most similar to your best customers
• A Custom Audience made up of everyone who has visited your website

You'd probably value reaching people in the first audience more than the second. Your best customers probably spend more money over longer periods of time, so a conversion from someone in the first audience may be worth more than one from someone in the second, who may have only visited your website once. This is a good reason to create two separate ad sets – one for each audience. Each should also have its own cost target based on its value.

If, instead, you had two different audiences that you valued reaching equally, it would be better to combine them into one ad set with a larger budget. It's better to have more budget concentrated over a few successful ad sets than less budget scattered across more under-performing ad sets. The former allows us to gather more data, which allows us to deliver your ads to people even more effectively.

Refine your targeting

As you increase your budget, you can run into targeting issues such as audience overlap and saturating your existing audiences. Here's how we recommend dealing with these issues.

Be aware of audience overlap

Audience is overlap is not necessarily a bad thing. It only becomes problematic when it leads to your ad sets being in the same auctions. When that happens, we automatically remove the lower-performing ad set to prevent you from competing against yourself. This can lead to it being delivered less.

This is important to bear in mind even if you haven't had problems with overlapping audiences in the past. You could've been using audiences that overlapped a lot, but your budgets were small enough that they never overlapped in auctions. However, to spend an increased budget your ad sets have to be entered into more auctions. This could lead to auction overlap.

Make sure that you check Delivery Insights to find out if auction overlap is causing performance issues, or check how much your audiences overlap in advance using the audience overlap tool.

If your audiences are overlapping in problematic ways, consider combining them into one ad set with a larger budget.

Use Lookalike Audiences to extend success

Lookalike Audiences allow you to build on the success of your existing audiences. They enable Facebook to find people similar to those in a "source" audience chosen by you. This is especially useful when increasing your budget. At a certain point, even the best audience may stop responding to your ads. In these cases, changing your targeting is a straightforward way to scale. Lookalike Audiences are the most powerful tool we have for scaling your targeting. This is because they allow you to find a new target audience while building on previously successful audiences.

For example, say you were using an engagement Custom Audience made up of people who liked your Page. You reach the point where your ads targeting that audience are becoming less effective. You could use this audience as a source for a Lookalike Audience. The Lookalike Audience would be made up of people similar to those who liked your Page.

If you're able to, we recommend using value-based Lookalike Audiences for maximising your return on ad spend.

Increase delivery flexibility

Delivery flexibility is important as you scale. We have to show your ads more in order to spend a higher budget. The more potential results we have to choose from, the more efficiently we can deliver your ads and the better chance we have of maintaining your cost target for longer. There are several ways to increase the flexibility our system has. We recommend:

• Targeting expansion: This feature gives us the option to expand your interest-based targeting if we think that doing so will get you better results. It lets you try targeting a specific audience without worrying that it could limit delivery, as we'll broaden the selected interests if necessary. (Note that this feature isn't currently available for ad sets in catalogue sales campaigns.)
• Automatic placement: This feature allows us to find the best results across all the places where Facebook can show ads (e.g. Instagram, Audience Network). As you increase your budget, this can help keep costs on target as our system will have more results to choose from.
• Campaign budget optimisation: This feature allows you to set a budget at the campaign level (rather than the ad set level). We then distribute that budget in real time to the best available results across all the ad sets in that campaign. It allows our system to be more nimble in seizing great opportunities for results when and where they appear. (Note that this feature is being tested and may not be available to you yet.)
• Worldwide targeting: If your products can be used or delivered globally, Facebook offers worldwide and regional targeting. This can greatly expand the reach of your campaigns, opening them up to a range of new (and potentially better) results. You can tell us to deliver your ads all over the world, or tell us to deliver them in specific regions (e.g. Europe, Asia) or free trade areas (e.g. NAFTA).

  We recommend using this type of targeting in conjunction with value-based optimisation products (value optimisation and app event optimisation) if you can. This will allow you to see if there are any differences in return on ad spend between regions. If there are, you can create ad sets with different cost targets as needed (see our campaign structure tips above). (Note that these products are being tested and may not be available to you yet.)
• Longer conversion windows: Our delivery system only uses conversions that happened within your conversion window to help us decide who else to show your ads to. We do this to make sure that we're getting results that are attributable to your ads. That said, if you've been using a one-day window but think up to seven days of consideration isn't unreasonable for your product/service, then try using a seven-day window. This can get us more conversion data to work with, which can help improve performance and keep costs on target.

Test your strategies

Being able to be adjust strategies quickly as the conditions of the marketplace change is a key element of maintaining success. Testing can help you do this, which can help you maintain your cost per result as you scale.

If you want to compare two variables in a strategy that you're using, we recommend running a split test if possible. Split tests may require a higher budget to get actionable results. Because of this, now is a great time to run one as you're increasing your budgets.

Here are some examples of variables that you could test:

• Static images vs video (or other variations in your creative)
• Lookalike Audiences based on your customer list vs Lookalike Audiences based on traffic to your website
• Different conversion windows (e.g. 7-day click vs 7-day click or 1-day view)

Get more out of your Facebook pixel or SDK

To further scale the success of your campaigns, we recommend implementing custom conversions and/or app events. Doing so allows you to:

• Measure more realistically. Tracking more signals gives you more insight into where the people you're reaching are dropping off in your marketing funnel. This information can help you make improvements to your website or app itself. Maybe your login experience or browsing flows are preventing people from making purchases. Once you've made the necessary improvements, your ads will be even more effective.
• Re-target people who dropped off before converting. Adding custom conversions and/or app events creates additional opportunities to capture potential converters that drop off before reaching your desired result. You can reach these people by creating audiences of people who have (or haven't) completed a certain custom conversion or app event.

Summary

With the target cost bid strategy, these best practices and a willingness to test and adjust, you can sustain successful campaigns at scale. This means getting more results from more people than ever before – without sacrificing the cost target that you're comfortable with.

* Nguồn: Facebook