The cue raise is one of the most important and common tools in the bag. Using it effectively is fairly simple most of the time, with a few slightly deeper ideas to think about at times.
The best way of explaining a cue raise is through examples
In this example you have 11 high card points, a nice useful small doubleton heart, some good intermediate cards (10's and 9's). Overall a very respectable hand. If a simple 2♠ raise shows say 6-10 points, this would be too strong. The solution is a cue raise - It is the bid of the opponent's suit, which shows a 3 card raise that is stronger than the simple raise (a bid of 2♠ here would be a simple raise).
The bid of 2♥ shows 11+ points and 3 card support. In this example partner just bid 2♠, basically saying - "I have a minimum overcall, opposite your 11-13 points I just want to play in 2♠." So, partner likely has around 9-10 points.
Note: You can have unlimited points when you cue raise, partner is always going to bid, partner will not pass 2♥. If, for example, you had 15 points in this hand, you could raise partner's 2♠ to game.
So, lets summarise what a cue raise is:
- A cue raise is the cue-bid of the opponents suit, to tell partner that you have 3 card support, and you are stronger than a simple raise. You do this at the lowest level (notice on the previous example you simply just bid 2♥, not 3♥).
As mentioned it is at the lowest level, but take this hand for example
On this example we show 11+ points and 3 card spade raise by bidding 3♦ (cue raising by bidding the opponent's suit). Notice on the example this time we had to cue raise on the 3 level.
A few extra things to add
1. Traditionally this bid is made by responder's first bid only. Notice the difference for example on this hand
On this example opener's bid of 3♥ is not a cue raise. With a good hand and spades opener just needs to raise spades to the appropriate level. A cue of the opponent's suit by opener just said "I have a good hand, better than a simple rebid of my suit".
Key takeaway: As opener, just raise partner to the appropriate level, cue raises are for responder's first bid only.
2. A cue raise with a passed hand shows the maximum end of a passed hand. So, for example
In this example you are a passed hand, so your cue raise now is about 9-11 points - the upper range of a passed hand. It is obviously not unlimited anymore since you passed initially! Therefore a simple raise in the example above would have been about 5-8 points.
The cue raise is a neat and simple way to show a good raise, the range of it depends on whether you are a passed hand or not - if you are not, the range is about 11+. The cue raise is used by every experienced partnership I've seen and I would describe it as one of the most essential and standard agreements in bridge.
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