As the year comes to a close, a lot of registration fees go up at the end of the month, so it makes sense to take a look around and see where the bargains (as well as extortionate prices) are before the annus horribilis 2016 is a thing of the past.¹ (Prices quoted are as of 12/28/17).
Not surprisingly, the most expensive race right now is July 8th Great American Naughtical Beer Mile. What a ripoff -- $32 dollars per mile!² But it comes with 4 beers, so its almost like they are paying you to run when you subtract the cost of the tasty Bluejacket beer. (Plus you get a medal/bottle opener if you finish)
Talking about expensive... The March 11 DC Rock n' Roll Half Marathon is quite pricey. Yes, the series is often discounted if you keep an eye peeled to their social media, but the closer you get to the race, the more unlikely that is. Right now the half marathon is a grotesque $105.99, which comes out to $8.10 per mile. You do get a forgettable t-shirt and medal as well. To be fair, you also get a well-run race (at least last year) with some decent course support. But compare a similar race later in the year - The September 17th Navy-Air Force Half Marathon at $80 comes out to $6.10 per mile (based on last year's pricing) for a nicer shirt and a smaller less crowded race experience (they also have race coupons online later in spring/summer). In comparison, the DC Rock n' Roll full is a veritable bargain at $115.99 -- $4.42 per mile, and it comes with a finisher premium jacket in addition to the shirt and the medal.
A good spring half marathon bargain is the B&A Marathon and Half Marathon on March 26th put on by the Annapolis Striders running club. At $65, the half is a little pricier at $5.34 per mile, but it has some of the best looking race premiums and medals out there. Register for the full at $70 and you pay a mere $2.67 per mile.
A big half marathon bargain is the Parks Half Marathon thrown by the Montgomery County Road Runners on September 10th, run on tree-lined asphalt trails in Montgomery County, MD. When registration opens on New Years Day, the fee will be $59 -- a mere $4.50 per mile, also coming with a nice long sleeve shirt, race medal, and additional premium. Another bargain is the October 28th Potomac River Run Half or Full Marathon run on the C&O towpath, at $60 or $4.58 per mile for the half and $2.79 per mile for the full (math!). That race has substandard premiums, but its hard to find a faster half marathon course out there (the full gets a little tedious, I've heard).
If you are feeling extremely cheap or poor, definitely look at the longer distances. The Mid-Maryland 50K on February 11th (run by local running legend and all-around nice guy Coach Phil Lang) is $60/$1.93 per mile. The Farm Park Challenge on May 6 is priced at $44 for the 10 hour race (51.8 miles). That comes out to an outrageous 85 cents per mile! (There's also a 6 or 3 hour race, as well as a marathon)
Another ultra bargain is the Seneca Creek Greenway Trail Marathon and 50K on March 4, also in Montgomery County and put on by the Montgomery County Road Runners. The 50K is $35 for non-club members, $25 for club members. The undiscounted race comes out to $1.12 per mile for non-members, so join and get the cheapest ultra (or any kind of race) around at 80 cents per mile (you also get a free half marathon -- Riley's Rumble -- and tens of other no-cost timed races thrown in as part of Montgomery Road Runners Club membership).
¹ Of course, this doesn't count some of the free fatass races like Redeye 50K put on by the Virginia Happy Trails Running Club on January 1 or Eternal Winter 50K on January 28th, thrown by Annapolis Striders. And it goes without saying, the wonderful free weekly DC Parkrun 5Ks at College Park, Roosevelt Island, and Fletcher's Cove.