Other than the typical coupons, Groupons, happy hours, and early bird specials, there are ways you can reduce your bill in a restaurant.
1. Have a drink and an appetizer at home first. This has become a tradition for me and my friends. First of all, it's nice to have some time at home to relax before going out. Secondly, it's a nice way to build excitement for your dinner. It also means you can order less food and less wine or cocktails at dinner. It's also easy; I usually make a little board with 2-4 of the following: cheese, fresh fruit, raw veggies, hummus, nuts, dried fruit (dates and apricots are nice), wasabi peas, salami, etc. (You can also tailor it to you health or diet goals.) Added bonus: If you are in a group, this lets that one friend who's always late off the hook.
2. If you are drinking alcohol, skip the soft drinks, iced tea, or coffee. They add at least $5-7 to your bill for two people once you add tax and tip.
3. Order a bottle of wine instead of glass pours. You will get more for your money. Many restaurants price their glasses as either a third or a fourth of the bottle cost to account for their spoilage liability. Typically you get 4 large or 5 medium glasses from 750ml. This is especially true for sparkling wine, as glass servings are smaller and you get much more.
4. Don't be afraid to ask your server for a budget-friendly recommendation! A great server will be happy to oblige. Just factor this in when you tip and give extra for the consideration (see my tipping note below).
5. Split an appetizer, salad, and an entree. Portions are generally huge, so this is usually plenty of food for two. It also lets you try more than if you just ordered entrees. If you are worried about a split plate charge, you can just say "We're sharing everything, so an extra plate would be great." If you are still hungry just order a dessert...
6. Order several appetizers as dinner. This is one of my favorite things to do because I like to try as many things on the menu as possible. Appetizer portions are typically larger than I expect, so we order 3 and it's usually perfect.
7. Go home for dessert and a nightcap. Personally, I find dessert to be the most frequently disappointing aspect of a restaurant meal. Nothing is worse than a stale, dry chocolate cake or a mushy 5-day-old tiramisu. Sometimes it is fantastic, but I usually prefer dark chocolate, sorbet, or gelato (or a great port or limoncello) from my own stash.
8. Call ahead if you are celebrating something (birthday, anniversary, etc) and mention it. Restaurants who do nothing special (free dessert, etc) for a special occasion are just lame.
On a side note, please remember to tip your server well. I always tip a little extra if I am purposely trying to lighten up my bill. Developing a repoire with a great server is also a nice way to get a fantastic experience on a repeat visit. Many of us have served at one point or another, and it is not an easy job. Nothing is more frustrating that the patrons who drink water and split the cheapest sandwich on the menu. I don't fault anyone for what they order, but I hope they realize that servers live off tips, not their sub-living-wage hourly pay. As in any industry, providing great service really adds to the experience and should be rewarded. In the restaurant industry, that means tipping well. Cheers to getting more for less!