Østfold is one of the 19 multi-member constituencies of the Storting, the national legislature of Norway. The constituency was established in 1921 following the introduction of proportional representation for elections to the Storting. It is conterminous with the county of Østfold. The constituency currently elects eight of the 169 members of the Storting using the open party-list proportional representation electoral system. At the 2025 parliamentary election it had 234,860 registered electors.

Electoral system Østfold currently elects eight of the 169 members of the Storting using the open party-list proportional representation electoral system. Constituency seats are allocated by the County Electoral Committee using the Modified Sainte-Laguë method. Compensatory seats (seats at large or levelling seats) are calculated based on the national vote and are allocated by the National Electoral Committee using the Modified Sainte-Laguë method at the constituency level (one for each constituency). Only parties that reach the 4% national threshold compete for compensatory seats.

Election results Summary Election CommunistsK RedsR / RV / FMS Socialist LeftSV / SF LabourAp GreensMDG CentreSp / Bp / L LiberalsV ChristianDemocratsKrF ConservativesH ProgressFrP / ALP colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 colspan=3 Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats Votes % Seats2025 9,236 5.20% 0 7,717 4.34% 0 52,961 29.80% 4 6,116 3.44% 0 8,570 4.82% 0 4,437 2.50% 0 6,858 3.86% 0 22,291 12.54% 1 51,055 28.73% 32021 7,418 4.58% 0 9,840 6.08% 0 49,345 30.48% 3 4,782 2.95% 0 22,849 14.11% 2 4,771 2.95% 0 5,414 3.34% 0 30,211 18.66% 2 20,527 12.68% 12017 3,435 2.14% 0 7,036 4.38% 0 51,545 32.05% 3 4,192 2.61% 0 13,943 8.67% 1 3,878 2.41% 0 6,811 4.24% 0 38,264 23.79% 2 28,181 17.52% 22013 1,149 0.73% 0 3,668 2.33% 0 54,910 34.92% 3 3,168 2.01% 0 6,405 4.07% 0 5,723 3.64% 0 8,828 5.61% 0 39,703 25.25% 3 30,801 19.59% 22009 1,041 0.70% 0 6,501 4.36% 0 58,613 39.34% 4 374 0.25% 0 7,250 4.87% 0 3,739 2.51% 0 8,589 5.76% 0 22,041 14.79% 1 38,853 26.08% 32005 107 0.07% 0 962 0.65% 0 10,721 7.23% 1 52,984 35.74% 3 180 0.12% 0 7,236 4.88% 0 5,943 4.01% 0 10,205 6.88% 0 17,697 11.94% 1 39,816 26.86% 32001 99 0.07% 0 776 0.55% 0 16,023 11.39% 1 39,191 27.85% 2 6,689 4.75% 0 3,501 2.49% 0 17,790 12.64% 1 27,514 19.55% 2 24,086 17.12% 21997 149 0.10% 0 2,227 1.55% 0 6,649 4.62% 0 57,713 40.09% 4 263 0.18% 0 10,013 6.96% 0 4,526 3.14% 0 19,218 13.35% 1 17,806 12.37% 1 22,841 15.87% 21993 741 0.54% 0 9,212 6.74% 0 57,962 42.43% 4 266 0.19% 0 19,435 14.23% 1 3,741 2.74% 0 11,739 8.59% 1 18,792 13.76% 1 10,067 7.37% 11989 757 0.50% 0 14,891 9.75% 1 60,902 39.89% 3 796 0.52% 0 9,116 5.97% 0 2,739 1.79% 0 12,789 8.38% 1 29,276 19.18% 2 20,661 13.53% 11985 217 0.14% 0 497 0.33% 0 5,562 3.66% 0 74,283 48.92% 4 9,240 6.09% 0 2,665 1.76% 0 13,351 8.79% 1 40,399 26.61% 3 4,440 2.92% 01981 428 0.29% 0 652 0.44% 0 4,798 3.27% 0 66,461 45.27% 4 9,869 6.72% 0 3,564 2.43% 0 13,300 9.06% 1 41,782 28.46% 3 5,414 3.69% 01977 481 0.35% 0 458 0.33% 0 4,222 3.08% 0 70,423 51.43% 5 10,663 7.79% 0 2,245 1.64% 0 16,084 11.75% 1 29,441 21.50% 2 1,792 1.31% 01973 417 0.32% 0 13,625 10.55% 1 55,670 43.12% 4 11,145 8.63% 1 1,750 1.36% 0 17,159 13.29% 1 22,265 17.24% 1 4,832 3.74% 01969 1,136 0.87% 0 4,381 3.34% 0 71,102 54.15% 5 13,264 10.10% 1 5,297 4.03% 0 13,566 10.33% 1 22,551 17.18% 1 1965 1,380 1.13% 0 8,051 6.57% 0 63,041 51.41% 4 14,713 12.00% 1 11,109 9.06% 1 24,330 19.84% 2 1961 3,532 3.12% 0 62,845 55.54% 4 12,507 11.05% 1 12,630 11.16% 1 21,645 19.13% 2 1957 2,982 2.73% 0 60,249 55.10% 5 9,065 8.29% 0 3,407 3.12% 0 12,935 11.83% 1 19,768 18.08% 2 1953 4,465 4.16% 0 58,120 54.20% 5 9,139 8.52% 1 3,810 3.55% 0 13,476 12.57% 1 18,229 17.00% 1 1949 2,781 3.92% 0 36,602 51.63% 3 10,299 14.53% 1 20,894 29.47% 2 1945 5,756 9.59% 0 25,283 42.12% 3 6,794 11.32% 1 1,990 3.32% 0 13,043 21.73% 1 7,162 11.93% 1 1936 29,840 49.04% 3 11,354 18.66% 1 5,728 9.41% 0 12,370 20.33% 2 1933 273 0.52% 0 24,744 47.26% 3 11,658 22.26% 2 5,632 10.76% 0 9,339 17.84% 1 1930 136 0.28% 0 17,937 36.66% 3 14,000 28.61% 2 5,278 10.79% 0 11,576 23.66% 1 1927 18,752 45.34% 3 11,226 27.15% 2 3,043 7.36% 0 8,334 20.15% 1 1924 387 1.01% 0 3,048 7.97% 0 10,708 28.00% 2 3,092 8.09% 0 9,806 25.64% 2 1921 3,251 9.77% 0 7,030 21.14% 1 3,773 11.34% 1 10,012 30.10% 2 (Excludes compensatory seats. Figures in italics represent joint lists.)

Detailed 2020s 2025 Results of the 2025 parliamentary election held on 8 September 2025:

Party Votes per municipality Totalvotes % SeatsAre-mark Fredrik-stad Halden Hvaler IndreØstfold Marker Moss Råde Rakke-stad Sarps-borg Skip-tvet Våler Labour Party Ap 191 15,789 5,692 1,002 6,495 656 9,376 1,118 1,225 10,198 506 713 52,961 29.80% 4 0 4 Progress Party FrP 179 13,816 4,979 925 7,981 492 7,478 1,407 1,417 10,418 817 1,146 51,055 28.73% 3 0 3 Conservative Party H 58 6,359 2,049 474 3,210 173 4,750 612 443 3,583 191 389 22,291 12.54% 1 0 1 Red Party R 42 2,665 1,064 158 1,181 93 1,896 160 177 1,561 91 148 9,236 5.20% 0 1 1 Centre Party Sp 234 1,231 818 139 2,172 369 652 359 779 1,160 294 363 8,570 4.82% 0 0 0 Socialist Left Party SV 18 2,543 682 110 1,026 46 1,597 155 112 1,268 64 96 7,717 4.34% 0 0 0 Christian Democratic Party KrF 81 1,780 783 94 1,067 188 701 317 332 1,242 130 143 6,858 3.86% 0 0 0 Green Party MDG 16 1,960 747 126 685 48 1,398 141 74 785 54 82 6,116 3.44% 0 0 0 Liberal Party V 7 1,327 400 126 585 48 1,089 86 56 615 29 69 4,437 2.50% 0 0 0 Pensioners' Party PP 8 764 375 31 275 14 390 52 34 432 21 27 2,423 1.36% 0 0 0 Norway Democrats ND 8 419 160 22 287 31 233 45 55 405 32 30 1,727 0.97% 0 0 0 Generation Party GP 8 298 103 13 215 18 218 34 33 203 23 32 1,198 0.67% 0 0 0 Industry and Business Party INP 11 284 262 12 133 7 130 35 31 156 22 21 1,104 0.62% 0 0 0 Conservative K 6 171 112 15 116 23 90 40 41 166 9 12 801 0.45% 0 0 0 Peace and Justice FOR 4 145 34 12 85 6 94 4 17 104 9 11 525 0.30% 0 0 0 Center Party PS 2 52 19 1 47 2 66 7 7 25 4 6 238 0.13% 0 0 0 DNI Party DNI 1 75 17 5 34 3 35 4 20 38 0 4 236 0.13% 0 0 0 Welfare and Innovation Party VIP 1 64 27 3 47 6 30 8 9 37 1 3 236 0.13% 0 0 0Valid votes 875 49,742 18,323 3,268 25,641 2,223 30,223 4,584 4,862 32,396 2,297 3,295 177,729 100.00% 8 1 9Blank votes 6 539 258 23 323 36 287 52 56 359 22 40 2,001 1.11% Rejected votes – other 0 19 64 11 60 1 69 16 3 96 5 2 346 0.19% Total polled 881 50,300 18,645 3,302 26,024 2,260 30,579 4,652 4,921 32,851 2,324 3,337 180,076 76.67% Registered electors 1,069 65,385 24,668 3,894 34,295 2,872 39,034 5,707 6,399 44,428 2,920 4,189 234,860 Turnout 82.41% 76.93% 75.58% 84.80% 75.88% 78.69% 78.34% 81.51% 76.90% 73.94% 79.59% 79.66% 76.67%

The following candidates were elected: Constituency seats - Hashim Abdi (Ap); Bjørnar Laabak (FrP); Julia Brännström Nordtug (FrP); Jon-Ivar Nygård (Ap); Tage Pettersen (H); Solveig Vitanza (Ap); Elise Waagen (Ap); and Erlend Wiborg (FrP). Compensatory seat - Remi Sølvberg (R).

2021 Results of the 2021 parliamentary election held on 13 September 2021:

Party Votes per municipality Totalvotes % SeatsAre-mark Fredrik-stad Halden Hvaler IndreØstfold Marker Moss Råde Rakke-stad Sarps-borg Skip-tvet Våler Labour Party Ap 159 14,892 5,299 862 5,731 623 8,326 962 945 10,451 469 626 49,345 30.48% 3 0 3 Conservative Party H 88 8,374 2,843 705 4,454 261 6,329 936 554 4,840 269 558 30,211 18.66% 2 0 2 Centre Party Sp 396 4,035 2,446 356 5,004 717 2,321 834 1,677 3,679 638 746 22,849 14.11% 2 0 2 Progress Party FrP 73 5,728 1,915 446 3,132 191 3,017 566 540 4,184 295 440 20,527 12.68% 1 0 1 Socialist Left Party SV 24 3,175 1,002 183 1,164 61 2,166 167 119 1,558 78 143 9,840 6.08% 0 1 1 Red Party R 26 2,362 925 158 831 56 1,471 126 114 1,170 70 109 7,418 4.58% 0 0 0 Christian Democratic Party KrF 63 1,403 623 60 840 133 525 277 257 1,032 92 109 5,414 3.34% 0 0 0 Green Party MDG 8 1,598 598 96 510 26 1,040 94 66 642 34 70 4,782 2.95% 0 0 0 Liberal Party V 12 1,449 458 85 650 48 1,201 99 45 600 36 88 4,771 2.95% 0 0 0 Democrats in Norway 8 522 252 42 453 26 329 45 61 486 60 64 2,348 1.45% 0 0 0 Pensioners' Party PP 4 673 292 28 171 14 249 45 13 357 13 10 1,869 1.15% 0 0 0 The Christians PDK 5 146 108 11 91 11 63 24 35 178 10 6 688 0.42% 0 0 0 Health Party 3 104 29 8 84 4 69 9 12 59 2 10 393 0.24% 0 0 0 Center Party 1 71 19 2 80 3 62 12 20 58 5 3 336 0.21% 0 0 0 People's Action No to More Road Tolls FNB 0 100 17 3 36 0 38 6 5 72 3 5 285 0.18% 0 0 0 Capitalist Party 1 67 40 1 26 6 46 4 6 61 1 4 263 0.16% 0 0 0 Industry and Business Party INP 0 67 21 7 31 1 38 9 10 34 5 7 230 0.14% 0 0 0 Alliance - Alternative for Norway 0 52 17 2 18 0 32 6 10 28 3 4 172 0.11% 0 0 0 Pirate Party of Norway 0 50 17 3 22 1 23 4 0 31 2 2 155 0.10% 0 0 0Valid votes 871 44,868 16,921 3,058 23,328 2,182 27,345 4,225 4,489 29,520 2,085 3,004 161,896 100.00% 8 1 9Blank votes 4 399 154 12 213 21 241 36 36 300 12 23 1,451 0.89% Rejected votes – other 0 56 47 4 28 12 15 12 2 31 0 0 207 0.13% Total polled 875 45,323 17,122 3,074 23,569 2,215 27,601 4,273 4,527 29,851 2,097 3,027 163,554 73.03% Registered electors 1,065 62,284 23,813 3,857 32,679 2,851 36,679 5,480 6,106 42,411 2,786 3,934 223,945 Turnout 82.16% 72.77% 71.90% 79.70% 72.12% 77.69% 75.25% 77.97% 74.14% 70.39% 75.27% 76.94% 73.03%

The following candidates were elected: Constituency seats - Elise Bjørnebekk-Waagen (Ap); Kjerstin Wøyen Funderud (Sp); Stein Erik Lauvås (Ap); Ole André Myhrvold (Sp); Jon-Ivar Nygård (Ap); Tage Pettersen (H); Ingjerd Schou (H); and Erlend Wiborg (FrP). Compensatory seat - Freddy André Øvstegård (SV).

2010s 2017 Results of the 2017 parliamentary election held on 11 September 2017:

Party Votes % Seats Labour Party Ap 51,545 32.05% 3 0 3 Conservative Party H 38,264 23.79% 2 0 2 Progress Party FrP 28,181 17.52% 2 0 2 Centre Party Sp 13,943 8.67% 1 0 1 Socialist Left Party SV 7,036 4.38% 0 1 1 Christian Democratic Party KrF 6,811 4.24% 0 0 0 Green Party MDG 4,192 2.61% 0 0 0 Liberal Party V 3,878 2.41% 0 0 0 Red Party R 3,435 2.14% 0 0 0 Pensioners' Party PP 1,359 0.85% 0 0 0 Health Party 806 0.50% 0 0 0 The Christians PDK 518 0.32% 0 0 0 Capitalist Party 353 0.22% 0 0 0 The Alliance 211 0.13% 0 0 0 Democrats in Norway 190 0.12% 0 0 0 Coastal Party KP 98 0.06% 0 0 0Valid votes 160,820 100.00% 8 1 9Blank votes 1,502 0.92% Rejected votes – other 392 0.24% Total polled 162,714 75.23% Registered electors 216,293

The following candidates were elected: Constituency seats - Elise Bjørnebekk-Waagen (Ap); Svein Roald Hansen (Ap); Stein Erik Lauvås (Ap); Ulf Leirstein (FrP); Ole André Myhrvold (Sp); Tage Pettersen (H); Ingjerd Schou (H); and Erlend Wiborg (FrP). Compensatory seat - Freddy André Øvstegård (SV).

2013 Results of the 2013 parliamentary election held on 8 and 9 September 2013:

Party Votes % Seats Labour Party Ap 54,910 34.92% 3 0 3 Conservative Party H 39,703 25.25% 3 0 3 Progress Party FrP 30,801 19.59% 2 0 2 Christian Democratic Party KrF 8,828 5.61% 0 1 1 Centre Party Sp 6,405 4.07% 0 0 0 Liberal Party V 5,723 3.64% 0 0 0 Socialist Left Party SV 3,668 2.33% 0 0 0 Green Party MDG 3,168 2.01% 0 0 0 Red Party R 1,149 0.73% 0 0 0 The Christians PDK 1,123 0.71% 0 0 0 Pensioners' Party PP 956 0.61% 0 0 0 Pirate Party of Norway 516 0.33% 0 0 0 Christian Unity Party KSP 145 0.09% 0 0 0 Democrats in Norway 99 0.06% 0 0 0 Coastal Party KP 68 0.04% 0 0 0Valid votes 157,262 100.00% 8 1 9Blank votes 895 0.57% Rejected votes – other 213 0.13% Total polled 158,370 75.76% Registered electors 209,038

The following candidates were elected: Constituency seats - Svein Roald Hansen (Ap); Irene Johansen (Ap); Stein Erik Lauvås (Ap); Ulf Leirstein (FrP); Eirik Milde (H); Ingjerd Schou (H); Bengt Morten Wenstøb (H); and Erlend Wiborg (FrP). Compensatory seat - Line Henriette Holten Hjemdal (KrF).

2000s 2009