How do area codes work in Winnipeg?

http://en.wikipedia.org/wiki/Area_codes_204_and_431

Area codes 204 and 431 are the North American telephone area codes for the Canadian province of Manitoba, encompassing the province.

In 2009 the Canadian Numbering Administrator forecast that area code 204 would be exhausted within a few years, despite there only being 1.2 million people in the entire province. While an area code typically holds 7.8 million possible numbers, Canada uses an inefficient allocation scheme in which competitive local exchange carriers receive 10,000-number blocks for even the smallest hamlets, with no number pooling. The situation was exacerbated by the proliferation of cell phones, particularly in Winnipeg.

In July 2010, the Canadian Radio-television and Telecommunications Commission approved a province-wide overlay with area code 431, for implementation in November 2012.^[1] On July 30, 2012, 10-digit dialing became mandatory throughout the province.^[2] This decision, rather than a geographical split of the area code, was made to spare rural Manitobans the expense and burden of having to change their numbers.

• Winnipeg (204) 200 201 202 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 235 237 250 251 253 254 255 256 257 258 259 260 261 262 269 272 275 282 283 284 285 287 289 290 291 292 293 294 295 296 297 298 299 318 330 333 334 336 338 339 360 390 391 396 399 410 414 415 416 417 421 430 451 452 453 470 471 474 475 477 478 479 480 487 488 489 499 500 504 505 509 510 514 515 557 558 560 582 583 586 588 589 590 594 599 612 615 619 631 632 633 654 661 663 666 667 668 669 688 691 694 695 697 698 760 770 771 772 774 775 777 779 780 781 782 783 784 786 787 788 789 790 791 792 793 794 795 797 798 799 800 801 802 803 804 805 806 807 808 809 813 815 831 832 833 837 869 880 881 885 887 888 889 890 891 894 895 896 897 898 899 910 914 918 919 920 924 925 926 927 928 929 930 931 932 933 934 935 936 938 940 941 942 943 944 945 946 947 948 949 951 952 953 954 955 956 957 958 959 960 962 963 975 977 979 981 982 983 984 985 986 987 988 989 990 992 995 996 997 998 999, (431) 200 222 318 433 485 777 800 845 944 999

Summary:

There weren't enough area codes to provide enough unique phone numbers for Winnipeg's population.

431 is the new area code that was added.